2. LEFT CLICK OR PRESS SPACE BAR TO ADVANCE, PRESS P BUTTON TO GO BACK, PRESS ESC BUTTON TO END LEFT CLICK OR PRESS SPACE BAR TO ADVANCE, PRESS P BUTTON TO GO BACK, PRESS ESC BUTTON TO END COMPUTER PRESENTATIONS FOR KS3 SCIENCE - PHYSICS ©2003, STEVE PARKER COMPUTER PRESENTATIONS FOR KS3 SCIENCE - PHYSICS ©2003, STEVE PARKER

3. 1 1 KS3 SCIENCE - PHYSICS KS3 SCIENCE - PHYSICS Energy Sources Energy Sources

4. WORK DONE 2 2

5. 3 3 “Work Done” = Force x Distance “Work Done” = Force x Distance

6. WORK DONE 4 4 1 Joule is the work done when a force of 1 N moves something 1 m 1 Joule is the work done when a force of 1 N moves something 1 m “Work Done” = Force x Distance

7. ENERGY 5 5

8. 6 6 “Energy” is something which can be used to produce work “Energy” is something which can be used to produce work

9. ENERGY 7 7 Different forms of energy include “Kinetic” energy (energy of movement) and “Potential” energy (energy due to height above the ground) Different forms of energy include “Kinetic” energy (energy of movement) and “Potential” energy (energy due to height above the ground)

10. ENERGY 8 8 Light energy is given off by bulbs and heat energy by toasters Light energy is given off by bulbs and heat energy by toasters The sun or a fire have both types of energy The sun or a fire have both types of energy

11. ENERGY 9 9 Electrical energy can be generated by batteries and sound energy is produced when something makes a noise Electrical energy can be generated by batteries and sound energy is produced when something makes a noise

12. ENERGY 10 Chemical energy is stored in foods and fuels, while strain energy is built up when something is stretched Chemical energy is stored in foods and fuels, while strain energy is built up when something is stretched

13. POWER 11

14. POWER 12 “Power” is the rate at which work is being done, i.e. work done per second “Power” is the rate at which work is being done, i.e. work done per second

15. POWER 13 “Power” is the rate at which work is being done, i.e. work done per second “Power” is the rate at which work is being done, i.e. work done per second If the rate of work = 1 J/s this is 1 Watt of power If the rate of work = 1 J/s this is 1 Watt of power

16. POWER 14 Power is not the same as force - it is to do with how much energy is transferred in a given period of time Power is not the same as force - it is to do with how much energy is transferred in a given period of time

17. SOURCES OF ENERGY 15

18. SOURCES OF ENERGY 16 One source of energy is the burning of fossil fuels (coal, oil and gas) One source of energy is the burning of fossil fuels (coal, oil and gas)

19. SOURCES OF ENERGY 17 But this source of energy cannot be renewed, and it produces several types of harmful emissions But this source of energy cannot be renewed, and it produces several types of harmful emissions

20. SOURCES OF ENERGY 18 Nuclear energy would last a long time and is relatively clean, except that nuclear waste needs to be stored and is very dangerous Nuclear energy would last a long time and is relatively clean, except that nuclear waste needs to be stored and is very dangerous

21. SOURCES OF ENERGY 19 Hydro-electric, tidal and wind energy is both renewable and clean Hydro-electric, tidal and wind energy is both renewable and clean

22. SOURCES OF ENERGY 20 Solar power can provide both heating and electricity and is renewable and clean, while in some countries geothermal energy is found Solar power can provide both heating and electricity and is renewable and clean, while in some countries geothermal energy is found