16146439-f1-c6-energy.docx

Science Form 1

Unit 6 Sources of Energy

6/5/2009 SMKBPJ(A) yschow

6.1

THE VARIOUS FORMS AND SOURCES OF ENERGY

6/5/2009 SMKBPJ(A) yschow

6.1 The Various Forms and Sources of E

Kinetic energy Chemical energy Electrical energy P

Light energy Sound energy Heat energy

6/5/2009 SMKBPJ(A) yschow

Potential energy

• Potential energy is the stored energy o position possessed by an object.

6/5/2009 SMKBPJ(A) yschow

Chemical energy

• Chemical Energy is energy stored in th of atoms and molecules. It is the energ holds these particles together.

• Biomass, petroleum, natural gas, and p are examples of stored chemical energ

6/5/2009 SMKBPJ(A) yschow

Nuclear energy

• Nuclear energy is energy obtained from the nucleus of some atoms.

Energy can be released fr in two ways: nuclear fusio nuclear fission.

The fuel most widely u by nuclear plants for nuclear fission is urani

6/5/2009 SMKBPJ(A) yschow

Nuclear plan

6/5/2009 SMKBPJ(A) yschow

Kinetic energy

• Kinetic energy is motion of objects.

• Moving water and wind are good exam kinetic energy.

6/5/2009 SMKBPJ(A) yschow

Heat Energy• The Sun is the main source of heat energy.

• Heat energy flows from a region with a higher

temperature to a region with a lower temperature.

• When heat energy is supplied to matter, its tempe

rises.

• Examples:

i. Burning fuels

ii. Sunshine

iii. Volcanic explosions and hot springs

iv.Electrical heaters

v.Substances taking part in chemical reactions

6/5/2009 SMKBPJ(A) yschow

Light Energy

• Light energy enables us to see things.

• The Sun is the main source of light energy a

known as solar energy.• Examples:

i. A burning candle or firewood

ii. Lightning flashes

iii. Lighted filament bulbs or fluorescent lamps

iv. The combustion of magnesium in oxygen

6/5/2009 SMKBPJ(A) yschow

Sound Energy

• Sound energy is produced by vibrations and in the form of waves through air.

• Sound energy can be transferred through sol liquids and gases but cannot travel through a vacuum.

• Examples:

i. Audio-visual aids and musical instruments

ii. A ticking clock

iii. A ringing bell.

6/5/2009 SMKBPJ(A) yschow

Mechanical Energy

• Mechanical energy is the total of kinetic energy a

potential energy possessed by an object.

• Mechanical energy is produced by machines or bodi changing their position.

• Examples: i. a pendulum clock that oscillates

ii. the downward and upward movement of a boy's l pedaling a bicycle

iii. the up and down movement of a see- saw

iv.the turning wheels of a vehicle

v.a rotating fan blade

6/5/2009 SMKBPJ(A) yschow

Electrical Energy

• Electrical energy is the energy carried by electric cur

• A large amount of electrical energy can be produced generators and power plants.

• Examples: i. A bicycle dynamo

ii. Solar cells and solar panels

iii. Generators in electric power stations

iv.Lightning

v.Batteries or dry cells

vi. Accumulators

6/5/2009 SMKBPJ(A) yschow

Conservation of Energy

• Energy cannot be created or destroyed.

• Energy can be transferred from one form to another.

• Energy converters changeone form of energy intoanother form.

6/5/2009 SMKBPJ(A) yschow

The Various Sources of Ene

Geothermal Solar WaterCoal

Firewood

Natural gas

Windandpetroleum

Waves BSMKBPJ(A) yschow6/5/2009

Fossil fuels

• Include coal, petroleum, natural gas.

6/5/2009 SMKBPJ(A) yschow

6/5/2009 SMKBPJ(A) yschow

How Is Petroleum Used

6/5/2009 SMKBPJ(A) yschow

Diesel

• Diesel can only be used in a diesel engi type of internal combustion engine use

many cars, boats, trucks, trains, buses, farm and construction vehicles.

6/5/2009 SMKBPJ(A) yschow

Petrol (Gasoline)

• Uses as fuel for car engines.

6/5/2009 SMKBPJ(A) yschow

Liquefied petroleum (LPG)

6/5/2009 SMKBPJ(A) yschow

Coal -- a fossil fuel

What is coal ? Where do we use co

Coal is a combustible black or brownish-black sedimentary rock composed mostly of carbon and hydrocarbons

6/5/2009 SMKBPJ(A) yschow

6/5/2009 SMKBPJ(A) yschow

HOW COAL IS USED

• FOR ELECTRIC POWER . Power plants burn coal to make steam. The turns turbines which generate electricity.

• FOR MAKING STEEL

Coal is baked in hot furnaces to make coke , used to smelt iron ore into iron needed for m steel.

"Coke" is a solid carbon made from coal6/5/2009 SMKBPJ(A) yschow

Radioactive substances

• Nuclear or radioactive substances such as ur and plutonium are used to produce nuclear

• Nuclear energy is used for

i. generating electrical energy

ii. supplying energy for submarines and ships

iii. producing atomic or hydrogen bombs

iv.supplying energy for satellites, meteorolo stations and lighthouses

6/5/2009 SMKBPJ(A) yschow

Geothermal source

• Geothermal energy is heat from within earth.

• We can use the steam and hot water

produced inside the earth to heat buil generate electricity

6/5/2009 SMKBPJ(A) yschow

Biomass fuels

• What is Biomass?

Biomass is organic material made from plants and animals.

• Methane is used as fuel to heat water and produce electrical energy.

6/5/2009 SMKBPJ(A) yschow

BIOMASS AS A TRANPSORTATION

6/5/2009 SMKBPJ(A) yschow

Environmental Benefits (Bio

• No net increase atmospheric ca dioxide.

• restore and ens stability and he along with mini chemical residu habitat destruc

6/5/2009 SMKBPJ(A) yschow

Water (hydro)

• The kinetic energy of water can be use generate hydroelectric energy.

• The production and use of hydroelectri energy does

not pollute the environme

Hydroelectric Plant6/5/2009 SMKBPJ(A) yschow

Wind

• Wind energy is used for

i. pumping water from ponds

ii. moving sailing ships at sea iii. turning wind turbines to generate

electrical energy

• It is also a non-polluting energy because

it does not produce any green house

effect gases.6/5/2009 SMKBPJ(A) yschow

Parts of An Electric generating Win

6/5/2009 SMKBPJ(A) yschow

Solar

• Solar Power is energy obtained by the the form of light.

• Solar energy is used for i. heating water in homes

ii. producing electrical energy

Photovoltaic (PV devices cells” – change sunlight di electricity

6/5/2009Solar panel

SMKBPJ(A) yschow

Solar energy can be collected by u various devices:

Solar cells.

Used in calculators, watches and satell

Solar panels.

i. Absorb heat energy from the Sun.

ii. Used to heat the water under the

iii. Usually found on rooftop.

Solar furnaces.

Generate electrical energy.

6/5/2009 SMKBPJ(A) yschow

The major disadvantages of solar e

• The amount of sunlight that arrives at t earth's surface is not constant. It depen location, time of day, time of year, and weather conditions.

• Because the sun doesn't deliver that m energy to any one place at any one tim large surface area is required to collect energy at a useful rate.

6/5/2009 SMKBPJ(A) yschow

Wave

• Waves are caused by the wind blowing the surface of the ocean. Waves have potential and kinetic energy.

• Waves can be used to generate electric energy through the movements of th connected to the power station.

wave energy plants

6/5/2009 SMKBPJ(A) yschow

TidesTides are caused by the gravitational pull of the moon and sun, and the rotation of the earth.

There are two-way systems that generate electricity on both the incoming and

outgoing tides.6/5/2009 SMKBPJ(A) yschow

Law of Conservation of Ene

• The law of conservation of energy says that energy is neither created nor destroyed.

• When we use energy, it doesn’t disappear.

• We change it from one form of energy into another.

6/5/2009 SMKBPJ(A) yschow

Energy Efficiency

• Energy efficiency is the amount of useful energy you get from a system.

6/5/2009 SMKBPJ(A) yschow

6.2

RENEWABLE AND NON - RENEWABLE

ENERGY SOURCES

6/5/2009 SMKBPJ(A) yschow

Nonrenewable and renewable e sources ?

Nonrenewable energy sources

• The sources of energy that can be replenished after

• they have been used and will never run out.

• Free and clean.

Renewable energy s

• The sources of en cannot be replenis

• after use.

• They are used up faster than they ca replaced.

6/5/2009 SMKBPJ(A) yschow

Renewable and Non-renewable Energy S

6/5/2009 SMKBPJ(A) yschow

The need to conserve ener

• The supply of energy in the form of fossil fuels is limited and it will be completely used up.

• Energy conservation is an important part of lessening climate change.

• Energy conservation facilitates the replacement of non-renewable resources with renewable energy.

6/5/2009 SMKBPJ(A) yschow

Efficient Use of Energy

• When a certain form of energy is used work, not all that energy is changed to energy.

• A certain part of the energy is usually as heat energy.

• The efficient use of energy is the fractio percentage of useful energy that does

6/5/2009 SMKBPJ(A) yschow

Example:

• A bulb changes only 5% of the electrica energy that is supplied to it to light ene

95% of the electrical energy is lost as h energy.

Buy energyefficient

Which do you use ? products.

6/5/2009 SMKBPJ(A) yschow

Some effective ways to use energy effic

1. Invest highly efficient equipment.

2. Construct buildings that use less ener

3. Develop uses of alternative energy so

6/5/2009 SMKBPJ(A) yschow

1. Effectiv

2. High-PeWindow

3. Tight Coand duc

4. EfficientCooling

5. Lighting

6/5/2009 SMKBPJ(A) yschow

6.3

THE IMPORTANCE OF CONSERV ENERGY SOURCES

6/5/2009 SMKBPJ(A) yschow

Use and Management of Energy So

• Energy sources are utilised in various fields:

a.Transport

b. Development

c.Telecommunication

d. Agriculture

e. Industry

6/5/2009 SMKBPJ(A) yschow

• Energy sources must be conserved bec they are very important to us in our da

• Alternative sources of energy which are should be used more often and more w

6/5/2009 SMKBPJ(A) yschow

• To conserve sources of firewood, trees be replanted to replace those that have cut down.

6/5/2009 SMKBPJ(A) yschow

What Can I Do to Save Ener

Energy conservation

• Energy conservation is any behavior that results in the use of less energy. Turning

the lights off when you leave the room and recycling aluminum cans are both ways of conserving energy.

Energy efficiency

• Energy efficiency i of technology that less energy to per same function.

6/5/2009 SMKBPJ(A) yschow

How Can Recycling Save Ene

• Recycling means to use something agai

• Newspapers can be used to make new newspapers.

• Aluminum cans can be used to make n aluminum cans.

• Glass jars can be used to make new gla

• Recycling often saves energy and natur resources through conservation.

6/5/2009 SMKBPJ(A) yschow