Student Handout Science F1

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SCIENCE TUSYEN 1.

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Chapter 4. DIVERSITY OF RESOURCES ON EARTH

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SCIENCE TUSYEN 3.

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SCIENCE TUSYEN.

FORM 1. CHAPTER 6.

SOURCES AND FORMS

OF ENERGY

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CHAPTER 7. HEAT AND ITS TRANSFER SCIENCE TUSYEN FORM 1

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ENERGY

POTENTIAL POTENTIAL ENERGY ENERGY CHEMICAL CHEMICAL ENERGY ENERGY KINETIC KINETIC ENERGY ENERGY HEAT HEAT ENERGY ENERGY LIGHT LIGHT ENERGY ENERGY SOUND SOUND ENERGY ENERGY ELECTRIVAL ELECTRIVAL ENERGY ENERGY NUCLEAR NUCLEAR ENERGY ENERGY MECHANICAL MECHANICAL ENERGY ENERGY

VARIOUS FORMS OF ENERGY

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OXYGEN IN AIR

CARBON DIOXIDE IN AIR

ANIMALS AND HUMANS

GREEN

PLANTS CARCASSES FOSSIL FUELS METALS

RUSTING

PHOTOSYNTHESIS

RESPIRATION

DECOMPOSITION

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SOURCES OF ENERGY ON EARTH

RENEWABLE

NON RENEWABLE

WIND WIND SOLAR SOLAR WAVES WAVES BIOMASS BIOMASS HYDRO HYDRO GEO THERMAL GEO THERMAL NUCLEAR

NUCLEAR _COAL_COAL

PETROLEUM PETROLEUM NATURAL GAS NATURAL GAS FOSSIL FUELS FOSSIL FUELS

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EXAMPLES OF ENERGY CONVERTER

ENERGY

CONVERTER

CONVERTER ENERGY CONVERSION

ENERGY CONVERSION

RADIO

RADIO Electrical energy sound energyElectrical energy sound energy TELEVISION

TELEVISION Electrical energy light energy sound Electrical energy light energy sound energy

energy

GAS STOVE

GAS STOVE Chemical energy heat energy light energy Chemical energy heat energy light energy

ELECTRIC FAN

ELECTRIC FAN Electrical energy kinetic energyElectrical energy kinetic energy BICYCLE

BICYCLE

DYNAMO

DYNAMO Kinetic energy electrical energy light Kinetic energy electrical energy light

energy

ELECTRIC IRON

ELECTRIC IRON Electrical energy heat energyElectrical energy heat energy HAIR-DRYER

HAIR-DRYER Electrical energy kinetic energy heat Electrical energy kinetic energy heat energy sound energy

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THE PRINCIPLE OF ENERGY CONSERVATION

~ Energy cannot be ~ Energy cannot be created or created or destroyed destroyed

~ Energy can only be

converted from one

form to another

ENERGY IS CONSERVED

Amount of energy Amount of energy

before conversion after conversion

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LIGHT ENERGY

(from the sun)

(from the sun) CHEMICAL ENERGY CHEMICAL ENERGY (in food) (in food) PHOTOSYNTHESIS PHOTOSYNTHESIS HEAT ENERGY + HEAT ENERGY + WATER + CARBON WATER + CARBON DIOXIDE DIOXIDE CHEMICAL ENERGY CHEMICAL ENERGY (in food)

(in food) RESPIRATIONRESPIRATION

PROCESSES AND ENERGY CONSERVATION

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COMPARISON BETWEEN

CONDUCTION, CONVECTION AND RADIATION

CONDUCTION

CONDUCTION CONVECTIONCONVECTION RADIATIONRADIATION ~ Transferred by

~ Transferred by

particles that vibrate

and collide with other

particles

~ Occurs in solids,

liquids and gases but

most effective in

solids

~ Does not occur in

a vacuum

~ Transferred by

particles that move

and form a and form a convectional current convectional current ~ Occurs in fluids ~ Occurs in fluids

Like liquids and gases

most effective

~ Does not occur in

a vacuum a vacuum ~ slow process ~ slow process ~ Radiated by a hot ~ Radiated by a hot body to surrounding body to surrounding

~ Occurs without any

medium medium ~ Can occur in ~ Can occur in a vacuum a vacuum

~ rapid process (light

Speed)

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USAGE OF THE PRINCIPLE OF HEAT

TRANSFER IN SOLVING PROBLEMS

COLD ROOM

Air heater and heating

Air heater and heating system ~ apply principle

HOT ROOM

1. the ventilation system of a

1. the ventilation system of a building ~ hot air rises out

CAR’S RADIATOR CAR’S RADIATOR ~ to remove heat ~ to remove heat produced in engine produced in engine by convection by convection through water in through water in the radiator the radiator THERMOS FLASK THERMOS FLASK

~ vacuum space prevent

heat loss by conduction

and convection

~ silver layered prevent

heat loss by radiation

TO WARM BODY

~ fire – to warm our

bodies prevent heat

transfer by radiation

from our body to

surrounding

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METHODS OF HEAT TRANSFER

CONDUCTION:

~ Heat transfer through

solid

solid from a high temperature from a high temperature to a low temperature

to a low temperature

CONVECTION:

~ Heat transfer in a

~ Heat transfer in a fluidfluid from from A hot to a less hot area

A hot to a less hot area

Examples of good Examples of good conductors are conductors are metal. metal. Copper Copper Aluminium Aluminium Iron Iron decreasedecrease RADIATION: RADIATION:

~ Heat transfer from a

heat source to its

surroundings without the

need of medium

(

(air or vacuumair or vacuum))

~ Hot fluid (less

dense) move up

~ Cold fluid (more

dense) move down

~ Can be absorbed or reflected

~ travel at speed of light

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CONDUCTORS

AND

INSULATORS

Materials that conduct

heat easily

Materials that do not

Conduct heat easily

Examples:

Metals ~ copper, iron

mercury, aluminium

Examples:

Wood, plastic, rubber,

water and air

Applications:

~ cooking utensils

~ radiator coil in vehicle

~ mercury – thermometer

~ wire gauze (steel)

Applications

~ handles of cooking utensils

~ polystyrene – food containers

~ fibreglass –refrigerators

~ sawdust – prevent ice melt

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NATURAL APPLICATION OF

THE PRINCIPLE OF CONVECTION

LAND BREEZE

LAND BREEZE SEA BREEZESEA BREEZE ~ at night, land cools faster

~ at night, land cools faster

than sea

~ hot air from the sea rises

and it is replaced by cold air

from the land

~ during day time, land heats

up faster than sea

~ hot air from the land rises

and it is replaced by cold air

from the sea

NATURAL APPLICATION OF

THE PRINCIPLE OF RADIATION

Earth and sun separated by vacuum. Heat from sun is transferred

To earth by radiation without the need of medium

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ABSORPTION

AND

RADIATION

All materials can absorb and radiate

DEPENDS ON:

1. surrounding temperature

~ object that has higher temperature than its surrounding,

radiates heat

~ object that has lower temperature than its surrounding,

absorbs heat

2. nature of its surface

~ dark and dull – best for absorbing heat

~ bright and shiny – best for reflecting heat

NATURE OF SURFACE

NATURE OF SURFACE _{HEAT ABSORPTION}_{HEAT ABSORPTION} _{HEAT RADIATION}_{HEAT RADIATION}

DULL

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