1. 1.1 Changes in energy stores
Energy is transferred from one energy store to another by:
* waves,
*an electric current,
*Heating
energy stores:
Chemical Kinetic gravitational elastic PE thermal
Energy can be stored in different ways
Increase in the Gravitational PE store
of the lift
Electric
Current in the wires
(This is the relevant change
to an energy store )

2. 1.1 Changes in energy stores
Energy is transferred from one energy store to another by:
* waves
*an electric current
*Heating
energy stores:
Chemical Kinetic gravitational elastic PE thermal
Energy can be stored in different ways
Increase in the Gravitational PE store
of the lift
Electric
Current in the wires
(This is the relevant change
to an energy store )

3. 1.1 Changes in energy stores
Energy is transferred from one energy store to another by:
* waves
*an electric current
*Heating
energy stores:
Chemical Kinetic gravitational elastic PE thermal
Energy can be stored in different ways
Increase in the Gravitational PE store
of the lift
Electric
Current in the wires
(This is the relevant change
to an energy store )

4. 1.1 Changes in energy stores
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot motor
Increase in the thermal energy store
of the motor
Caused by the work done
against the force of friction
Increase in the gravitational PE store
of the lift
Electric
Current in the wires
Caused by the lift
rising at a steady speed
Increase in the thermal energy store of the surroundings.
Caused by the sound waves from the lift machinery

5. 1.1 Changes in energy stores
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot motor
Increase in the thermal energy store
of the motor
Caused by the work done
against the force of friction
Increase in the gravitational PE store
of the lift
This does not equal
the KE of the lift!
Electric
Current in the wires
Caused by the lift
rising at a steady speed
Increase in the thermal energy store of the surroundings.
Caused by the sound waves from the lift machinery

6. 1.1 Changes in energy stores
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot motor
Increase in the thermal energy store
of the motor
Caused by the work done
against the force of friction
Increase in the gravitational PE store
of the lift
This does not equal
the KE of the lift!
Electric
Current in the wires
Caused by the lift
rising at a steady speed
Increase in the thermal energy store of the surroundings.
Caused by the sound waves from the lift machinery

7. 1.1 Changes in energy stores
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot motor
Increase in the thermal energy store
of the motor
Caused by the work done
against the force of friction
Increase in the gravitational PE store
of the lift
This does not equal
the KE of the lift!
Electric
Current in the wires
Caused by the lift
rising at a steady speed
Increase in the thermal energy store of the surroundings.
Caused by the sound waves from the lift machinery

8. 1.9 Changes in energy stores
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot motor
Increase in the thermal energy store
of the motor
Caused by the work done
against the force of friction
Increase in the gravitational PE store
of the lift
This does not equal
the KE of the lift!
Electric
Current in the wires
Caused by the lift
rising at a steady speed
Increase in the thermal energy store of the surroundings.
Caused by the sound waves from the lift machinery
( less than 1% )

9. 1.9 Energy and power

20. Multiples and prefixes
symbol
example
x ( x 1000)
x ( x 1,000,000)
x 109
x 1012
x 1015
x 1018
kilo k km
mega M MΩ
giga G GW
tera T
THz
peta P Ps
exa E Em
also, but rarely used: deca = x 10, hecto = x 100

21. 2 million kettles at 3kW each = 6GW
Mains filament lamp
10,000 W cooker
2 million kettles at 3kW each = 6GW
P= E so E = Pt t
E = 5000W x 20s
E = 100,000 J

22. 2 million kettles at 3kW each = 6GW
Mains filament lamp
10,000 W cooker
2 million kettles at 3kW each = 6GW
P= E so E = Pt t
E = 5000W x 20s
E = 100,000 J

23. 2 million kettles at 3kW each = 6GW
Mains filament lamp
10,000 W cooker
2 million kettles at 3kW each = 6GW
P= E so E = Pt t
E = 5000W x 20s
E = 100,000 J

24. 2 million kettles at 3kW each = 6GW
Mains filament lamp
10,000 W cooker
2 million kettles at 3kW each = 6GW
P= E so E = Pt t
E = 5000W x 20s
E = 100,000 J
% efficiency = OP energy x 100%
IP energy
= 12, x 100%
100,000
= 12%

25. 2 million kettles at 3kW each = 6GW
Mains filament lamp
10,000 W cooker
2 million kettles at 3kW each = 6GW
P= E so E = Pt t
E = 5000W x 20s
E = 100,000 J
% efficiency = OP energy x 100%
IP energy
= 12, x 100%
100,000
= 12%

26. 2 million kettles at 3kW each = 6GW
Mains filament lamp
10,000 W cooker
2 million kettles at 3kW each = 6GW
P= E so E = Pt t
E = 5000W x 20s
E = 100,000 J
% efficiency = OP energy x 100%
IP energy
= 12, x 100%
100,000
= 12%

27. a. P = E t
P =

28. a. P = E t
P = 1,500,000 J s
P =

29. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P =

30. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P = 30,000 W
P =

31. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P = 30,000 W
P = kW

32. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P = 30,000 W
P = kW b.
% efficiency = OP power x 100%
IP power
= 30kW x 100%
100kW
= %

33. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P = 30,000 W
P = kW b.
% efficiency = OP power x 100%
IP power
= 30kW x 100%
100kW
= %

34. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P = 30,000 W
P = kW b.
% efficiency = OP power x 100%
IP power
= 30kW x 100%
100kW
= %

35. a. P = E t
P = 1,500,000 J s
P = 1,500, W 50
P = 30,000 W
P = kW b.
% efficiency = OP power x 100%
IP power
= 30kW x 100%
100kW
= %

36. Increase in the thermal energy store
of the
Electric
Current in the wires
Increase in the thermal energy store of the
Caused by the
heating from
the hot shower heater
( less than 1% )

37. Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )

38. P= E so E = Pt t E = 12 kW x (20 x60 x4 ) s E = 12 k W x 4800 s
E = 57,600 kJ
E = MJ
Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )

39. P= E so E = Pt t E = 12 kW x (20 x60 x4 ) s E = 12 k W x 4800 s
E = 57,600 kJ
E = MJ
Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )

40. P= E so E = Pt t E = 12 kW x (20 x60 x4 ) s E = 12 k W x 4800 s
E = 57,600 kJ
E = MJ
Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )

41. P= E so E = Pt t E = 12 kW x (20 x60 x4 ) s E = 12 k W x 4800 s
E = 57,600 kJ
E = MJ
Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )

42. P= E so E = Pt t E = 12 kW x (20 x60 x4 ) s E = 12 k W x 4800 s
E = 57,600 kJ
E = MJ
Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )

43. P= E so E = Pt t E = 12 kW x (20 x60 x4 ) s E = 12 k W x 4800 s
E = 57,600 kJ
E = MJ
Increase in the thermal energy store
of the water
Electric
Current in the wires
Increase in the thermal energy store of the surroundings.
Caused by the
heating from
the hot shower heater
( less than 1% )