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Thermal Energy
Thermal Energy
How does thermal energy work?
Important terms to know:
Temperature:
Important terms to know:
Temperature: A measure of the average kinetic energy of the individual particles in matter.
Important terms to know:
Temperature: A measure of the average kinetic energy of the individual particles in matter. Low temperatures = low kinetic
energy
Important terms to know:
Temperature: A measure of the average kinetic energy of the individual particles in matter. Low temperatures = low kinetic
energy High temperatures = high kinetic
energy
Important terms to know:
Temperature: continued Thermometers: As the liquid in
the thermometer heats up its volume increases (rises) and as it cools off its volume goes down (drops).
Important terms to know:
Temperature: continued Scales: The three common scales are
Fahrenheit, Celsius, and the Kelvin scales.
Important terms to know:
Temperature: continued Scales: The three common scales are
Fahrenheit, Celsius, and the Kelvin scales.
Fahrenheit: Used in the United States.
Important terms to know:
Temperature: continued Scales: The three common scales are
Fahrenheit, Celsius, and the Kelvin scales.
Fahrenheit: Used in the United States.Celsius: Used nearly everywhere else.
Important terms to know:
Temperature: continued Scales: The three common scales are
Fahrenheit, Celsius, and the Kelvin scales.
Fahrenheit: Used in the United States.Celsius: Used nearly everywhere else.Kelvin: Commonly used in the physical
sciences.
Important terms to know:
Temperature: continued Conversions:
Important terms to know:
Temperature: continued Conversions: °K = °C + 273
Important terms to know:
Temperature: continued Conversions: °K = °C + 273 °C = °K - 273
Important terms to know:
Temperature: continued Conversions: °K = °C + 273 °C = °K - 273 °C = 5/9(°F – 32)
Important terms to know:
Temperature: continued Conversions: °K = °C + 273 °C = °K - 273 °C = 5/9(°F – 32) °F = 9/5°C + 32
Thermal Energy:
Thermal Energy depends on:
Thermal Energy:
Thermal Energy depends on: the number of particles an object has.
Thermal Energy:
Thermal Energy depends on: the number of particles an object has. the temperature of an object.
Thermal Energy:
Thermal Energy depends on: the number of particles an object has. the temperature of an object. the arrangement of the object’s particles.
Thermal Energy:
Thermal Energy depends on: the number of particles an object has. the temperature of an object. the arrangement of the object’s particles.
Heat:
Thermal Energy:
Thermal Energy depends on: the number of particles an object has. the temperature of an object. the arrangement of the object’s particles.
Heat: Thermal energy that moves from a warmer
object to a cooler object.
Thermal Energy:
Thermal Energy depends on: the number of particles an object has. the temperature of an object. the arrangement of the object’s particles.
Heat: Thermal energy that moves from a warmer
object to a cooler object. Thermal energy only becomes heat when it
is transferred.
Thermal Energy: Thermal Energy depends on:
the number of particles an object has. the temperature of an object. the arrangement of the object’s particles.
Heat: Thermal energy that moves from a warmer
object to a cooler object. Thermal energy only becomes heat when it
is transferred. It’s unit of measure is “Joules”.
Thermal Energy:
Specific Heat:
Thermal Energy:
Specific Heat: The amount of energy required to raise 1 g of a material by 1 °C.
Thermal Energy:
Specific Heat: The amount of energy required to raise 1 g of a material by 1 °C.
Measured in joules per kilogram-Celsius
Thermal Energy:
Specific Heat: The amount of energy required to raise 1 g of a material by 1 °C.
Measured in joules per kilogram-Kelvin J/(kg*C)
Thermal Energy:
Common specific heats: Aluminum: 903 J/(kg*C) Copper 385 Glass 837 Ice 2,060 Iron 450 Sand 800 Water 4,180
Heat Transfer:
Heat is transferred by three different methods.
Heat Transfer:
Heat is transferred by three different methods. Conduction: The transfer of heat
without the movement of matter.
Heat Transfer:
Heat is transferred by three different methods. Conduction: The transfer of heat
without the movement of matter.A metal spoon in a pan of hot water
(the spoon gets hot over time).
Heat Transfer:
Heat is transferred by three different methods. Convection: The transfer of heat
by the movement of currents within a fluid.
Heat Transfer:
Heat is transferred by three different methods. Convection: The transfer of heat
by the movement of currents within a fluid.
Water heating up in a pot on the stove (you can see the water moving).
Heat Transfer:
Heat is transferred by three different methods. Convection: The transfer of heat
by the movement of currents within a fluid.
Water heating up in a pot on the stove (you can see the water moving).
Convection currents?!?!
Convection current:H
eating
U
p
The circular flow is due to the heating and cooling of
molecules which changes their density.
Molecules:
HOT !!!
Co
olin
g
Off
Cool !!!
Heat Transfer:
Heat is transferred by three different methods. Radiation: The transfer of energy
by electromagnetic waves.
Heat Transfer:
Heat is transferred by three different methods. Radiation: The transfer of energy
by electromagnetic waves.A fireplace warming a room.
Heat Transfer:
Heat is transferred by three different methods. Radiation: The transfer of energy
by electromagnetic waves.A fireplace warming a room.Does not require matter to transfer
thermal energy (the sun).
Heat Transfer:
Heat flow:
Heat Transfer:
Heat flow: Heat transfer goes in one
direction.
Heat Transfer:
Heat flow: Heat transfer goes in one
direction.Heat leaves the warmer object and
goes to the cooler object.
Heat Transfer:
Heat flow: Heat transfer goes in one
direction.Heat leaves the warmer object and
goes to the cooler object.This will continue until the two
objects have the same temperature.
Heat Transfer: Conductors:
Heat Transfer: Conductors: A material that transfers
thermal energy well, partially because its atoms or molecules are close together.
Heat Transfer: Conductors: A material that transfers
thermal energy well, partially because its atoms or molecules are close together. Silver Stainless steel tile
Heat Transfer: Conductors: A material that transfers
thermal energy well, partially because its atoms or molecules are close together. Silver Stainless steel tile
Insulators:
Heat Transfer: Conductors: A material that transfers
thermal energy well, partially because its atoms or molecules are close together. Silver Stainless steel tile
Insulators: A material that does not transfer thermal energy very well, partially because its atoms or molecules are not closely packed together.
Heat Transfer: Conductors: A material that transfers thermal
energy well, partially because its atoms or molecules are close together. Silver Stainless steel tile
Insulators: A material that does not transfer thermal energy very well, partially because its atoms or molecules are not closely packed together. Wood Wool Paper Atmospheric gases
Thermal Expansion:
Does matter matter with thermal energy?
Matter:
What is matter?
Matter:
What is matter? Has mass
Matter:
What is matter? Has mass Takes up space (has volume)
Matter:The three states of matter:
Matter:The three states of matter:
SolidsHas a fixed shapeHas a fixed volume
Matter:The three states of matter:
SolidsHas a fixed shapeHas a fixed volume
LiquidsHas a shape that can changeHas a fixed volume
Matter:The three states of matter:
SolidsHas a fixed shapeHas a fixed volume
LiquidsHas a shape that can changeHas a fixed volume
GasesHas a shape that can change.Has a volume that can change.
Matter:
Matter:The fourth state of matter is
plasma.
Matter:The fourth state of matter is
plasma. Plasma is the highest energy state of
matter (moving super fast).
Matter:The fourth state of matter is
plasma. Plasma is the highest energy state of
matter (moving super fast). Very, very, very, very, very hot!!!
Matter:The fourth state of matter is
plasma. Plasma is the highest energy state of
matter (moving super fast). Very, very, very, very, very hot!!! Found in places like our sun.
Matter:The fourth state of matter is
plasma. Plasma is the highest energy state of
matter (moving super fast). Very, very, very, very, very hot!!! Found in places like our sun. Not always considered a state of
matter.
Matter:Changes in states of matter:
Matter:Changes in states of matter:
Matter can change from any state to any other state by adding energy.
Matter:Changes in states of matter:
Matter can change from any state to any other state by adding energy.
The temperature does not change until the change of state is complete.
Thermal Expansion:
When an object is heated it usually responds to the heat.
Thermal Expansion:
When an object is heated it usually responds to the heat. One response is for the particles
of the object to move faster and spread out (increasing volume).
Thermal Expansion:
When an object is heated it usually responds to the heat. One response is for the particles
of the object to move faster and spread out (increasing volume).
This causes the object to expand and is called thermal expansion.
Thermal Expansion examples:
When thermometers are exposed to warmer temperatures.
Thermal Expansion examples:
When thermometers are exposed to warmer temperatures.
Thermostats in your home.
Thermal Expansion examples:
When thermometers are exposed to warmer temperatures.
Thermostats in your home.Sidewalks
Thermal Expansion examples:
When thermometers are exposed to warmer temperatures.
Thermostats in your home.SidewalksBridges
Thermal Expansion examples:
When thermometers are exposed to warmer temperatures.
Thermostats in your home.SidewalksBridgesJars (pickles, jelly, etc…)
Thermal Expansion:
Contraction:
Thermal Expansion:
Contraction:1. The heat source gets removed.
Thermal Expansion:
Contraction:1. The heat source gets removed.
2. The particles move less and take up less space.
Thermal Expansion:
Contraction:1. The heat source gets removed.
2. The particles move less and take up less space.
3. The size of the object decreases.