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Thermodynamics
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THERMODYNAMICSTHERMO
DYNAMICS
TEMPERATURE AND THERMAL ENERGY
TEMPERATURE AND THERMAL ENERGY
Thermal energy ndash a form of kinetic energy characterized by randomness of motion at the atomic and molecular level
Thermal energy ndash a form of kinetic energy characterized by randomness of motion at the atomic and molecular level
Temperature ndash the degree or intensity of heat present in a substance or object the measure of the hotness or coldness of a body
Temperature ndash the degree or intensity of heat present in a substance or object the measure of the hotness or coldness of a body
Heat ndash the energy transit from a body of higher temperature to one of lower temperature under the influence of the variation in temperature quantity of thermal energy absorbed or given off by a body
Heat ndash the energy transit from a body of higher temperature to one of lower temperature under the influence of the variation in temperature quantity of thermal energy absorbed or given off by a body
LETrsquoS DO THISLETrsquoS DO THIS
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
QUESTIONShellipQUESTIONShellip
1 Which of the 2 beakers has thermal energy1 Which of the 2 beakers has thermal energy
2 Which of the 2 beakers has greater temperature
2 Which of the 2 beakers has greater temperature
3 Which of the 2 beakers contains more heat3 Which of the 2 beakers contains more heat
ANSWERShellipANSWERShellip
1 Both fluids inside the beaker have thermal energy
1 Both fluids inside the beaker have thermal energy
2 Both have the same temperature2 Both have the same temperature
3 The beaker filled with hot water up to the brim contains greater heat
3 The beaker filled with hot water up to the brim contains greater heat
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
TEMPERATURE AND THERMAL ENERGY
TEMPERATURE AND THERMAL ENERGY
Thermal energy ndash a form of kinetic energy characterized by randomness of motion at the atomic and molecular level
Thermal energy ndash a form of kinetic energy characterized by randomness of motion at the atomic and molecular level
Temperature ndash the degree or intensity of heat present in a substance or object the measure of the hotness or coldness of a body
Temperature ndash the degree or intensity of heat present in a substance or object the measure of the hotness or coldness of a body
Heat ndash the energy transit from a body of higher temperature to one of lower temperature under the influence of the variation in temperature quantity of thermal energy absorbed or given off by a body
Heat ndash the energy transit from a body of higher temperature to one of lower temperature under the influence of the variation in temperature quantity of thermal energy absorbed or given off by a body
LETrsquoS DO THISLETrsquoS DO THIS
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
QUESTIONShellipQUESTIONShellip
1 Which of the 2 beakers has thermal energy1 Which of the 2 beakers has thermal energy
2 Which of the 2 beakers has greater temperature
2 Which of the 2 beakers has greater temperature
3 Which of the 2 beakers contains more heat3 Which of the 2 beakers contains more heat
ANSWERShellipANSWERShellip
1 Both fluids inside the beaker have thermal energy
1 Both fluids inside the beaker have thermal energy
2 Both have the same temperature2 Both have the same temperature
3 The beaker filled with hot water up to the brim contains greater heat
3 The beaker filled with hot water up to the brim contains greater heat
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
Heat ndash the energy transit from a body of higher temperature to one of lower temperature under the influence of the variation in temperature quantity of thermal energy absorbed or given off by a body
Heat ndash the energy transit from a body of higher temperature to one of lower temperature under the influence of the variation in temperature quantity of thermal energy absorbed or given off by a body
LETrsquoS DO THISLETrsquoS DO THIS
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
QUESTIONShellipQUESTIONShellip
1 Which of the 2 beakers has thermal energy1 Which of the 2 beakers has thermal energy
2 Which of the 2 beakers has greater temperature
2 Which of the 2 beakers has greater temperature
3 Which of the 2 beakers contains more heat3 Which of the 2 beakers contains more heat
ANSWERShellipANSWERShellip
1 Both fluids inside the beaker have thermal energy
1 Both fluids inside the beaker have thermal energy
2 Both have the same temperature2 Both have the same temperature
3 The beaker filled with hot water up to the brim contains greater heat
3 The beaker filled with hot water up to the brim contains greater heat
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
LETrsquoS DO THISLETrsquoS DO THIS
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Materials
1 beaker half filled with hot water1 beaker filled with hot water up to the brim2 ice cubesStopwatch
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
Procedure
Drop the cubes to the individual beakersSee what happens (Observe the rate by which the ice cube melts)
QUESTIONShellipQUESTIONShellip
1 Which of the 2 beakers has thermal energy1 Which of the 2 beakers has thermal energy
2 Which of the 2 beakers has greater temperature
2 Which of the 2 beakers has greater temperature
3 Which of the 2 beakers contains more heat3 Which of the 2 beakers contains more heat
ANSWERShellipANSWERShellip
1 Both fluids inside the beaker have thermal energy
1 Both fluids inside the beaker have thermal energy
2 Both have the same temperature2 Both have the same temperature
3 The beaker filled with hot water up to the brim contains greater heat
3 The beaker filled with hot water up to the brim contains greater heat
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
QUESTIONShellipQUESTIONShellip
1 Which of the 2 beakers has thermal energy1 Which of the 2 beakers has thermal energy
2 Which of the 2 beakers has greater temperature
2 Which of the 2 beakers has greater temperature
3 Which of the 2 beakers contains more heat3 Which of the 2 beakers contains more heat
ANSWERShellipANSWERShellip
1 Both fluids inside the beaker have thermal energy
1 Both fluids inside the beaker have thermal energy
2 Both have the same temperature2 Both have the same temperature
3 The beaker filled with hot water up to the brim contains greater heat
3 The beaker filled with hot water up to the brim contains greater heat
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
ANSWERShellipANSWERShellip
1 Both fluids inside the beaker have thermal energy
1 Both fluids inside the beaker have thermal energy
2 Both have the same temperature2 Both have the same temperature
3 The beaker filled with hot water up to the brim contains greater heat
3 The beaker filled with hot water up to the brim contains greater heat
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
MEASURING TEMPERATUREMEASURING TEMPERATURE
1 Using the tactile sense1 Using the tactile sense
2 Using a thermometer2 Using a thermometer
PARTS OF A THERMOMETERPARTS OF A THERMOMETER
a Thermal sensora Thermal sensor
b Calibrations ~ degF degC or Kb Calibrations ~ degF degC or K
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
TYPES OF THERMOMETERTYPES OF THERMOMETER
1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer1 Dial thermometer ndash aka Rotary thermometer
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
2 Glass thermometer ndash aka liquid-in-glass ~2 Glass thermometer ndash aka liquid-in-glass ~ Mercury or Colored alcoholMercury or Colored alcohol
3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer 3 Thermocouple ndash aka electronic thermometer
4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer4 Liquid crystal thermometer
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
TEMPERATURE SCALESTEMPERATURE SCALES
11 Fahrenheit ScaleFahrenheit Scale ndash (named after Ger ndash (named after Ger physicist physicist Gabriel Daniel FahrenheitGabriel Daniel Fahrenheit) based ) based on the freezing and boiling point of water at on the freezing and boiling point of water at normal atmospheric pressure ~ 32normal atmospheric pressure ~ 32ordmF - ordmF - freezing pt and 212ordmF ndash boiling ptfreezing pt and 212ordmF ndash boiling pt
2 Celsius Scale2 Celsius Scale ndash (named after Swed ndash (named after Swed astronomer astronomer Anders C CelsiusAnders C Celsius) based on the ) based on the freezing and boiling point of water at freezing and boiling point of water at normal atmospheric pressure ~ 0normal atmospheric pressure ~ 0ordmC - ordmC - freezing pt and 100ordmC ndash boiling ptfreezing pt and 100ordmC ndash boiling pt
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
3 Kelvin Scale3 Kelvin Scale ndash (named after Brit physicist ndash (named after Brit physicist William T KelvinWilliam T Kelvin) erased the arbitrary ) erased the arbitrary assigned reference points thus called not a assigned reference points thus called not a relative scalerelative scale but an but an Absolute temperature Absolute temperature scalescale 0 0 = nothing ndash = nothing ndash Absolute ZeroAbsolute Zero ~ lowest ~ lowest temperature possible occurring when all temperature possible occurring when all random motion of molecules has ceased In random motion of molecules has ceased In this scale 273K ndash freezing pt of water this scale 273K ndash freezing pt of water 373K ndash boiling pt373K ndash boiling pt
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
CONVERSIONSCONVERSIONS
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
bull From degF to degC (degF -32)59
bull From degC to degF (degC 95) + 32
bull From degC to KdegC + 273
bull From degF to K(degF-32)59 + 273
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
It is easier to open a tight bottle cap by exposing it to heat
It is easier to open a tight bottle cap by exposing it to heat
THERMAL EXPANSIONTHERMAL EXPANSION
EXPANSION OF MATERIALSEXPANSION OF MATERIALS
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials expand as their thermal energy increasesrdquo rarr Thermal
expansion
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
ldquoMaterials contract as their thermal energy decreasesrdquo
ldquoMaterials contract as their thermal energy decreasesrdquo
EXPANSION OF MATERIALS UNDER 100degCEXPANSION OF MATERIALS UNDER 100degC
Materials Materials
(1 m in length)(1 m in length)
Length of Length of ExpansionExpansion
Invar (alloy of Fe and Ni)Invar (alloy of Fe and Ni) 01 mm01 mm
Pyrex Pyrex 03 mm03 mm
Platinum alloyPlatinum alloy 09 mm09 mm
GlassGlass 09 mm09 mm
ConcreteConcrete 10 mm10 mm
SteelSteel 10 mm10 mm
BrassBrass 20 mm20 mm
AluminumAluminum 30 mm30 mm
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
ldquoModern bridges are usually constructed withldquoModern bridges are usually constructed with
a One end attached while the other end rests on rollers
a One end attached while the other end rests on rollers
b With tooth like seams called expansion joints
b With tooth like seams called expansion joints
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
THERMOSTATTHERMOSTAT
ldquoThe amount of expansion of a material depends on the change in temperaturerdquoldquoThe amount of expansion of a material depends on the change in temperaturerdquo
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
The device that regulates the temperature of a material is called a thermostat It is usually consists of bimetallic strips eg Brass (alloy of Cu and Zn) and Fe that are welded together When the Brass side is heated it expands and contracts when cooled rarr can help turn onoff a device such as heaters
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
HEAT TRANSFERHEAT TRANSFER
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
The study of the flow of heat within an object or from one medium to another due to their variation in temperature
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
1 Radiation - energy is emitted in the form of electromagnetic waves or subatomic particles eg heatwarmth felt from a flame or bonfire sans touching it the heat from the microwave oven and the heat from the sun
METHODS OF HEAT TRANSFER METHODS OF HEAT TRANSFER
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
2 Conduction - heat energy transfer caused by direct contact wherein heat travels from one molecule to another For example exposing metal to a flame allowing an article to rest on a warm or hot object
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
ldquoHeat flows from a region of high concentration to a region of low concentrationrdquo
Hot rarr ColdHot rarr Cold
LegendLegend
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
3 Convection - transference of mass or heat within a fluid caused by the tendency of warmer and less dense material to rise producing air or fluid currents
Hot air risesHot air rises Air cools down becomes denseAir cools down becomes dense
Cold air sinksCold air sinksAir heats up and becomes less
dense
Air heats up and becomes less
dense
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
SPECIFIC HEATSPECIFIC HEAT
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
The amount of energy required to raise the temperature of one kilogram (1 kg) of a substance by one degC (1degC) or one Kelvin (1 K) It is expressed in terms of Joules per kilogram-Kelvin (JkgmiddotK) or Joules per kilogram degree Celsius (JkgmiddotdegC) or calorie per gram degree Celcius (calgmiddotdegC) in which 1 cal = 4186 J
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
THERMAL CAPACITYTHERMAL CAPACITY
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
The amount of heat required to raise the temperature of a substance by 1 degree (1deg) and is the product of its mass and specific heat
ΔQ = mCΔTΔQ = mCΔT
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
Wherein ΔQ is change in heat expressed in terms of Jm is the mass of the substance in kgC is the specific heat in JkgmiddotKΔT is the change in heat in K
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
WORD PROBLEMSWORD PROBLEMS
1 How much heat is needed to raise the temperature of 150 kg of water to 323 K1 How much heat is needed to raise the temperature of 150 kg of water to 323 K
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup
2 What is the temperature of the mixture of 075 kg of water at 98degC is added to 05kg of water at 25degC in a polystyrene cup