SCIENCE TUSYEN 1.
FORM 1. Chapter 3. MATTER
Chapter 4. DIVERSITY OF RESOURCES ON EARTH
SCIENCE TUSYEN 3.
FORM 1. Chapter 5. AIR AROUND US
SCIENCE TUSYEN. SCIENCE TUSYEN. FORM 1. CHAPTER 6. FORM 1. CHAPTER 6.
SOURCES AND FORMS SOURCES AND FORMS OF ENERGYOF ENERGY
CHAPTER 7. HEAT AND ITS TRANSFERSCIENCE TUSYEN FORM 1
ENERGYENERGY
POTENTIAL POTENTIAL ENERGY ENERGY
CHEMICAL CHEMICAL ENERGY ENERGY
KINETIC KINETIC ENERGYENERGY
HEAT HEAT ENERGYENERGY
LIGHT LIGHT ENERGYENERGY
SOUND SOUND ENERGYENERGY
ELECTRIVAELECTRIVAL ENERGYL ENERGY
NUCLEAR NUCLEAR ENERGYENERGY
MECHANICAL MECHANICAL ENERGY ENERGY
VARIOUS FORMS OF ENERGY VARIOUS FORMS OF ENERGY VARIOUS FORMS OF ENERGY VARIOUS FORMS OF ENERGY
OXYGEN IN AIR
CARBON DIOXIDE IN AIR
ANIMALS AND HUMANS
GREEN PLANTS
CARCASSES FOSSIL FUELS METALS
RUSTINGPHOTOSYNTHESIS
RESPIRATION
DECOMPOSITION
COMBUSTION
SOURCES OF ENERGY ON EARTHSOURCES OF ENERGY ON EARTHSOURCES OF ENERGY ON EARTHSOURCES OF ENERGY ON EARTH
RENEWABLERENEWABLE NON RENEWABLENON RENEWABLE
WINDWIND
SOLARSOLAR
WAVESWAVES
BIOMASSBIOMASS
HYDROHYDRO
GEO THERMALGEO THERMAL
NUCLEARNUCLEAR COALCOAL
PETROLEUMPETROLEUM
NATURAL GASNATURAL GAS
FOSSIL FUELSFOSSIL FUELS
EXAMPLES OF ENERGY CONVERTEREXAMPLES OF ENERGY CONVERTEREXAMPLES OF ENERGY CONVERTEREXAMPLES OF ENERGY CONVERTER
ENERGY ENERGY CONVERTERCONVERTER
ENERGY CONVERSIONENERGY CONVERSION
RADIORADIO Electrical energy sound energyElectrical energy sound energy
TELEVISIONTELEVISION Electrical energy light energy sound Electrical energy light energy sound energyenergy
GAS STOVEGAS STOVE Chemical energy heat energy light Chemical energy heat energy light energy energy
ELECTRIC FANELECTRIC FAN Electrical energy kinetic energyElectrical energy kinetic energy
BICYCLE BICYCLE DYNAMODYNAMO
Kinetic energy electrical energy light Kinetic energy electrical energy light energyenergy
ELECTRIC ELECTRIC IRONIRON
Electrical energy heat energyElectrical energy heat energy
HAIR-DRYERHAIR-DRYER Electrical energy kinetic energy heat Electrical energy kinetic energy heat energy sound energyenergy sound energy
ELECTRIC RICE ELECTRIC RICE COOKERCOOKER
Electrical energy heat energyElectrical energy heat energy
LIGHT BULBLIGHT BULB Electrical energy heat energy light Electrical energy heat energy light energyenergy
THE PRINCIPLE OF ENERGY CONSERVATIONTHE PRINCIPLE OF ENERGY CONSERVATIONTHE PRINCIPLE OF ENERGY CONSERVATIONTHE PRINCIPLE OF ENERGY CONSERVATION
~ Energy cannot be ~ Energy cannot be created orcreated ordestroyeddestroyed
~ Energy can only be~ Energy can only beconverted from oneconverted from one
form to anotherform to another
ENERGY IS CONSERVEDENERGY IS CONSERVEDAmount of energy Amount of energyAmount of energy Amount of energybefore conversion after conversionbefore conversion after conversion
LIGHT ENERGYLIGHT ENERGY(from the sun)(from the sun)
CHEMICAL ENERGYCHEMICAL ENERGY(in food)(in food)PHOTOSYNTHESISPHOTOSYNTHESIS
HEAT ENERGY + HEAT ENERGY + WATER + CARBONWATER + CARBON
DIOXIDEDIOXIDE
CHEMICAL ENERGYCHEMICAL ENERGY(in food)(in food)
RESPIRATIONRESPIRATION
PROCESSES AND ENERGY CONSERVATIONPROCESSES AND ENERGY CONSERVATIONPROCESSES AND ENERGY CONSERVATIONPROCESSES AND ENERGY CONSERVATION
COMPARISON BETWEEN COMPARISON BETWEEN CONDUCTION, CONVECTION AND RADIATION CONDUCTION, CONVECTION AND RADIATION
CONDUCTIONCONDUCTION CONVECTIONCONVECTION RADIATIONRADIATION
~ Transferred by ~ Transferred by particles that vibrateparticles that vibrateand collide with otherand collide with otherparticlesparticles
~ Occurs in solids,~ Occurs in solids,liquids and gases butliquids and gases butmost effective inmost effective insolidssolids
~ Does not occur in~ Does not occur ina vacuuma vacuum
~ rapid process~ rapid process
~ Transferred by ~ Transferred by particles that moveparticles that moveand form a and form a convectional currentconvectional current
~ Occurs in fluids ~ Occurs in fluids Like liquids and gasesLike liquids and gasesmost effective most effective
~ Does not occur in~ Does not occur ina vacuuma vacuum
~ slow process~ slow process
~ Radiated by a hot ~ Radiated by a hot body to surroundingbody to surrounding
~ Occurs without any ~ Occurs without any mediummedium
~ Can occur in~ Can occur ina vacuuma vacuum
~ rapid process (light~ rapid process (lightSpeed)Speed)
USAGE OF THE PRINCIPLE OF HEAT USAGE OF THE PRINCIPLE OF HEAT TRANSFER IN SOLVING PROBLEMSTRANSFER IN SOLVING PROBLEMS
COLD ROOM COLD ROOM Air heater and heatingAir heater and heatingsystem ~ apply principle system ~ apply principle of convection, fixed at lower of convection, fixed at lower Section. Hot air which producedSection. Hot air which producedmoves up while the cold air moves up while the cold air moves down moves down
HOT ROOMHOT ROOM1. the ventilation system of a1. the ventilation system of abuilding ~ hot air rises out building ~ hot air rises out through upper section (air holes) through upper section (air holes) 2. air conditioner ~ apply 2. air conditioner ~ apply principle of convection, fixed at principle of convection, fixed at upper section upper section
CAR’S RADIATORCAR’S RADIATOR~ to remove heat~ to remove heatproduced in engineproduced in engineby convection by convection through water in through water in the radiator the radiator
THERMOS FLASKTHERMOS FLASK~ vacuum space prevent~ vacuum space preventheat loss by conduction heat loss by conduction and convectionand convection~ silver layered prevent~ silver layered preventheat loss by radiationheat loss by radiation
TO WARM BODYTO WARM BODY~ fire – to warm our ~ fire – to warm our bodies prevent heatbodies prevent heattransfer by radiationtransfer by radiationfrom our body tofrom our body tosurrounding surrounding
METHODS OF HEAT TRANSFERMETHODS OF HEAT TRANSFER
CONDUCTION:CONDUCTION:~ Heat transfer through~ Heat transfer throughsolidsolid from a high temperature from a high temperatureto a low temperatureto a low temperature
CONVECTION:CONVECTION:~ Heat transfer in a ~ Heat transfer in a fluidfluid from from A hot to a less hot areaA hot to a less hot area
Examples of good Examples of good conductors areconductors aremetal.metal.
CopperCopperAluminiumAluminiumIronIron decreasedecrease
RADIATION:RADIATION:~ Heat transfer from a ~ Heat transfer from a heat source to its heat source to its surroundings without thesurroundings without the need of medium need of medium ((air or vacuumair or vacuum))
~ Hot fluid (less ~ Hot fluid (less dense) move updense) move up~ Cold fluid (more~ Cold fluid (moredense) move downdense) move down
~ Can be absorbed or reflected~ Can be absorbed or reflected~ travel at speed of light ~ travel at speed of light
CONDUCTORSCONDUCTORS INSULATORSINSULATORSANDAND
Materials that conductMaterials that conductheat easilyheat easily
Materials that do not Materials that do not Conduct heat easilyConduct heat easily
Examples:Examples:Metals ~ copper, ironMetals ~ copper, ironmercury, aluminiummercury, aluminium
Examples:Examples:Wood, plastic, rubber,Wood, plastic, rubber,
water and airwater and air
Applications:Applications:~ cooking utensils~ cooking utensils~ radiator coil in vehicle~ radiator coil in vehicle~ mercury – thermometer~ mercury – thermometer~ wire gauze (steel)~ wire gauze (steel)~ heating coil – electric kettle~ heating coil – electric kettle~ soldering iron – made of ~ soldering iron – made of coppercopper~ Davy safety light~ Davy safety light
ApplicationsApplications~ handles of cooking utensils~ handles of cooking utensils~ polystyrene – food containers~ polystyrene – food containers~ fibreglass –refrigerators~ fibreglass –refrigerators~ sawdust – prevent ice melt~ sawdust – prevent ice melt~ fur clothing – keep body warm~ fur clothing – keep body warm~ blanket – keep body warm~ blanket – keep body warm~ igloo ~ igloo ~ sleeping bag ~ sleeping bag
NATURAL APPLICATION OF NATURAL APPLICATION OF THE PRINCIPLE OF CONVECTION THE PRINCIPLE OF CONVECTION
LAND BREEZELAND BREEZE SEA BREEZESEA BREEZE
~ at night, land cools faster~ at night, land cools fasterthan seathan sea~ hot air from the sea rises ~ hot air from the sea rises and it is replaced by cold airand it is replaced by cold airfrom the landfrom the land
~ during day time, land heats~ during day time, land heatsup faster than seaup faster than sea~ hot air from the land rises ~ hot air from the land rises and it is replaced by cold airand it is replaced by cold airfrom the seafrom the sea
NATURAL APPLICATION OFNATURAL APPLICATION OFTHE PRINCIPLE OF RADIATIONTHE PRINCIPLE OF RADIATION
Earth and sun separated by vacuum. Heat from sun is transferredEarth and sun separated by vacuum. Heat from sun is transferredTo earth by radiation without the need of medium To earth by radiation without the need of medium
ABSORPTIONABSORPTION RADIATIONRADIATIONANDAND
All materials can absorb and radiateAll materials can absorb and radiate
DEPENDS ON:DEPENDS ON:1. surrounding temperature1. surrounding temperature ~ object that has higher temperature than its surrounding, ~ object that has higher temperature than its surrounding, radiates heatradiates heat~ object that has lower temperature than its surrounding, ~ object that has lower temperature than its surrounding, absorbs heatabsorbs heat2. nature of its surface2. nature of its surface~ dark and dull – best for absorbing heat~ dark and dull – best for absorbing heat~ bright and shiny – best for reflecting heat~ bright and shiny – best for reflecting heat
NATURE OF NATURE OF SURFACESURFACE
HEAT HEAT ABSORPTIONABSORPTION
HEAT RADIATIONHEAT RADIATION
DULLDULL GOODGOOD GOODGOOD
SHINYSHINY BADBAD BADBAD
BRIGHTBRIGHT BADBAD BADBAD
DARKDARK GOODGOOD GOODGOOD