16146439-f1-c6-energy.docx
TRANSCRIPT
Science Form 1
Unit 6 Sources of Energy
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6.1
THE VARIOUS FORMS AND SOURCES OF ENERGY
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6.1 The Various Forms and Sources of E
Kinetic energy Chemical energy Electrical energy P
Light energy Sound energy Heat energy
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Potential energy
• Potential energy is the stored energy o position possessed by an object.
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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
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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
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Nuclear plan
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Kinetic energy
• Kinetic energy is motion of objects.
• Moving water and wind are good exam kinetic energy.
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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
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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
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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.
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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
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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
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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.
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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.
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How Is Petroleum Used
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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.
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Petrol (Gasoline)
• Uses as fuel for car engines.
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Liquefied petroleum (LPG)
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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
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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
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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
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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.
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BIOMASS AS A TRANPSORTATION
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Environmental Benefits (Bio
• No net increase atmospheric ca dioxide.
• restore and ens stability and he along with mini chemical residu habitat destruc
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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
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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
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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.
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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.
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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
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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.
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Energy Efficiency
• Energy efficiency is the amount of useful energy you get from a system.
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6.2
RENEWABLE AND NON - RENEWABLE
ENERGY SOURCES
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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.
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Renewable and Non-renewable Energy S
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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.
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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
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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.
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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
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1. Effectiv
2. High-PeWindow
3. Tight Coand duc
4. EfficientCooling
5. Lighting
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6.3
THE IMPORTANCE OF CONSERV ENERGY SOURCES
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Use and Management of Energy So
• Energy sources are utilised in various fields:
a.Transport
b. Development
c.Telecommunication
d. Agriculture
e. Industry
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• 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
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• To conserve sources of firewood, trees be replanted to replace those that have cut down.
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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.
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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.
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