1. Energy Resources & Energy Transfers

2. Forms of Energy
List the main forms of energy...

3. Objectives Identify the main forms of energy.
Construct energy transfer diagrams, identifying useful and wasted energy transfers.

4. Conservation of Energy
The law of conservation of energy states

5. Forms of Energy
Light
Sound
Kinetic
Heat

6. Forms of Energy Electrical Chemical Potential Gravitational Potential
Elastic
Potential

7. seen in different forms
Forms of Energy
Estelle
Mrs Snewin
Florist
Sister
Gravitational
Potential
Chemical
Potential
Mum
Daughter
Energy
Sound
Electrical
Elastic
Potential
Same person/thing
seen in different forms
Heat
Kinetic
Light

8. Useful Energy Transferred Wasted Energy Transferred
Forms of Energy
Copy and complete the following table:
Device
Useful Energy Transferred
Wasted Energy Transferred

9. Gravitational Potential
Kinetic
Electrical
Elastic Potential
Sound
Light
Heat
Chemical Potential
Gravitational Potential

10. Objectives
Construct Sankey diagrams to show how much energy is transferred as different forms.
Calculate efficiency.

11. Sankey Diagrams Heat Energy Electrical Energy
Old-style light bulb...  
Heat
Energy
90 J
9 cm
100 J
10 cm  
10 J
Electrical
Energy
Light
Energy

12. Sankey Diagrams Draw a Sankey diagram to show:
A kettle which transforms 1000 J of electrical energy into 900 J of heat energy in the water and 100 J of wasted heat and sound energy.

13. Wasted Heat & Sound Energy
Kettle
Heat
Energy in Water 
1000 J
900 J
10 cm 
100 J
Electrical
Energy
Wasted Heat & Sound Energy

14. Sankey Diagrams Draw a Sankey diagram to show:
A toaster which transforms 1000 J of electrical energy into 300 J of heat energy in the bread and 700 J of wasted heat and sound energy.

15. Wasted Heat & Sound Energy
Toaster
Heat
Energy in bread 
300 J
1000 J
10 cm
700 J 
Electrical
Energy
Wasted Heat & Sound Energy

16. Sankey Diagrams Draw a Sankey diagram to show:
A hair dryer which transforms 1000 J of electrical energy into 500 J of kinetic energy, 100 J of heat energy in the hair, and 400 J wasted as heat and sound energy.

17. Wasted Heat & Sound Energy
Hair Dryer
Kinetic
Energy 
500 J
1000 J
10 cm
400 J 
Wasted Heat & Sound Energy
100 J
Electrical
Energy
Heat Energy
in Hair

18. Efficiency
Efficiency is a measure of how much of the energy that is transferred during a process goes towards doing something useful. e.g. a filament light bulb converts 100 J of electrical energy to 10 J of light energy and 90 J of heat energy. Calculate the efficiency.

19. Efficiency
A new energy efficient light bulb converts 100 J of electrical energy to 60 J of light energy and 40 J of heat energy. Calculate the efficiency.
A kettle transfers 4000 J of electrical energy into 3920 J of heat energy in the water, and 80 J of energy wasted as sound and heat in the surroundings. Calculate the efficiency.

21. Objectives Calculate the kinetic energy of objects.
Calculate the gravitational potential energy of objects.
Explain how to convert between the two and identify the wasted energy transfers.

22. e- Kinetic Energy Mass – 9.11x10-31 kg Velocity – 7.6x106 m/s
Mass – 227 kg Velocity – 0.16 mph / 0.07 m/s
Mass – 5.97x1024 kg Velocity – 30 km/s
Mass – kg Velocity – 570 mph / 255 m/s
Mass – 620 kg Velocity – 180 mph / 80 m/s

23. Kinetic Energy e-

24. Kinetic energy = ½ x mass x velocity squared
The amount of kinetic energy an object has can be found using the formula:
Kinetic energy = ½ x mass x velocity squared
(J) (kg) (m/s) KE v2
½ m
KE = ½ mv2

25. Kinetic Energy Example:
Calculate the velocity of an F1 car with a mass of 600 kg and a KE of J.
Calculate the mass of an athlete running with KE 1600 J at 8 m/s.

26. Kinetic Energy
Emily drives her car at a speed of 30 m/s. If the combined mass of her and the car is 1000 kg what is her kinetic energy?
Catia rides her bike at a speed of 10 m/s. If the combined mass of Jessica and her bike is 60 kg what is her kinetic energy?
Dan is running and has a kinetic energy of 750 J. If his mass is 60 kg how fast is he running?
George is walking to town. If he has a kinetic energy of 150 J and he’s walking at a pace of 2 m/s what is his mass?

27. GPE
Why is it harder to climb than to fall?.

28. GPE Mass – 15 kg Height – 6 m Mass – 60 kg Height – 5 m

29. GPE
Gravitational potential energy is the energy stored when an object increases in height.
GPE = mass x gravitational field strength x height
(J) (kg) (N/kg) (m)
GPE h m g
GPE = mgh

30. GPE
A kg aeroplane takes off and ascends to a height of 1000 m. How much gravitational potential energy has been transferred to the plane?
A skateboarder (80 kg) starts a run by rolling 3 m down a half pipe. How much GPE has been transferred?
A man (90 kg) moves from the 3rd floor of a building to the 5th floor. The height between each floor is 3 m – how much GPE is transferred?

31. Which Has More Energy? Mass: 5 kg Height: 12 m Mass: 50 kg
Velocity: 25 m/s

32. Which Has More Energy? Mass: 20 g Height: 3 m Mass: 1000 kg
Velocity: 0 m/s

33. Which Has More Energy? Mass: 500 000 kg Height: 10 000m
Mass: 1.67x10-27 kg
Velocity: m/s

34. Which Has More Energy? Mass: 80 kg Height: 29 m Mass: 80 kg
Velocity: 21.5 m/s

35. GPE & KE

37. GPE & KE
Mr. Snewin is rather careless and he drops his laptop out of the window, 1 m above the ground. The laptop has a mass of 3 kg; how fast will it hit the ground?
GPE = mgh = 3 x 10 x 1 = 30 J
As the laptop hits the ground all of the GPE has been converted to KE. GPE = KE
GPE = KE = 30 J = ½ mv2.
v2 = 30/ ½ m = 30/1.5 = 20
v = √20
v = 4.5 m/s

38. GPE & KE
A 70 kg base-jumper has an unfortunate experience as he leaps off a 50 m building and finds his parachute won’t open.
How fast will he hit the ground if his back-up parachute doesn’t work?
Find GPE.
Find KE.
Rearrange and find v.

39. GPE & KE Any moving object will have ______ energy.
Any object moved to a ______ position will gain ______________ potential energy.
When an object such as a pendulum is released the _________ energy is transformed to ________ energy.
The object cannot reach the same _______ again due to some energy being wasted as _____ and ______.
Words: height weight higher lower heat potential gravitational kinetic kinetic sound

40. Extension
Using the equations for GPE and KE, prove that all objects will fall at the same speed, and that mass has no effect on this speed.

41. Objectives
Calculate the work done in moving objects.

42. Work Done
When any object is moved around work will need to be done on it to get it to move (obviously).
We can work out the amount of work done in moving an object using the formula:
Work done = Force x Distance Moved
(J) (N) (m) W d F
W = Fd

43. Work Done
Jennifer pushes a book 5 m along the table with a force of 5 N. She gets tired and decides to call it a day. How much work did she do?
Megan lifts a laptop 2 m into the air with a force of 10 N. How much work does she do?
Gemma does 200 J of work by pushing a wheelbarrow with a force of 50 N. How far did she push it?
Savannah cuddles her cat and lifts it 1.5 m in the air. If she did 75 J of work how much force did she use?

44. Recap Questions
How much kinetic energy would Richard have if he travelled at a speed of 5 m/s and has a mass of 70 kg?
Olivia does some work by pushing a box around with a force of 1 N. She does 50 J of work and decides to call it a day. How far did she push it?
A lift with a mass of 500 kg rises through 10 m. How much GPE does the lift gain?
875 J
50 m J

45. Power
Power is defined as the rate of energy transfer; i.e. how much energy is transferred every second.
We can work out power using the formula:
Power = Energy Transferred / Time
(W) (J) (s) E t P
P = E / t

46. Dr. Octopus
Mass: 110 kg

47. Power
A drill is used for 8 seconds and transfers 2400 J of energy. What is the power rating of the drill?
Jenny uses a 500 W toaster for 2 minutes to make her breakfast. How much energy did she use?
Sarah uses a 3 kW kettle and transfers a total amount of J of energy. How long was the kettle on for?

48. Energy to drive a car 60 miles: 250,000,000 J
Energy stored in 1 litre of petrol: 34,000,000 J
Energy used by the human body for 1 day: 10,000,000 J
Energy in 1 unit on electricity bill (costs 15p): 3,600,000 J
Energy in a typical chocolate bar: 1,000,000 J
Energy to boil 1 L of water, from freezing: 500,000 J
Energy stored in a peanut: ,000 J
Kinetic energy of a fast-moving cricket ball: J
Energy stored in one new AA battery: J
Energy from burning one whole match: J
Energy to lift up an apple by one metre: 1 J
Energy to make the human heart beat once: ½ J
Energy to press key on computer keyboard: 1/100 J

49. Quiz! What is the gravitational field strength on Earth? A. 10 N/kg
B. 1 N/kg
C. 1 kg/N
D. 10 kg/N

50. Quiz! What is the formula for calculating work done?
A. Work Done = Force / Distance
B. Work Done = Force x Distance
C. Work Done = Distance / Force
D. Work Done = Force x Mass

51. Quiz! How much work is done if a 30 kg mass is lifted through 2 m?
A. 60 J
B. 15 J
C. 150 J
D. 600 J

52. Quiz!
How much gravitational potential energy does a 30 kg mass gain if it is lifted through 2 m?
A. 60 J
B. 15 J
C. 150 J
D. 600 J

53. Quiz!
How much kinetic energy does a 5000 kg car have when moving at 10 m/s?
A J
B J
C J
D J

54. Quiz!
A light bulb transfers 3600 J of energy in one minute. What is the power of the bulb?
A. 100 W
B. 40 W
C. 60 W
D. 80 W

55. Quiz!
How much energy does Amy’s W microwave transfer in 3 minutes?
A. 800 J
B. 4.4 J
C J
D J

56. Quiz!
A cheetah runs at a top speed of 32 m/s, and has a kinetic energy of J. What is the mass of the cheetah?
A. 30 kg
B. 60 kg
C. 90 kg
D. 120 kg

57. Quiz!
A 80 kg man runs up the stairs and gains 4800 J of GPE. Each floor is 2 m high. How many floors did he climb?
A. 1
B. 2
C. 3
D. 4

58. Homework Reflection I am good at/need to improve:
Using KE and GPE equations.
Rearranging KE & GPE equations.
Applying the law of conservation of
energy.

59. Energy Resources

60. in the turbines and the generator
Coal Power Stations
Chemical Potential Energy
Heat Energy
Kinetic Energy
Kinetic Energy
Electrical Energy
stored in the fuel
in the water.
in the water
in the turbines and the generator
in the cables.

61. Solar Power
Light Energy
Electrical Energy
from the Sun
in the cables.

62. in the turbines and the generator
Wind Power
Kinetic Energy
Kinetic Energy
Electrical Energy
in the wind
in the turbines and the generator
in the cables.

63. in the turbines and the generator
Hydroelectric Power
Gravitational Potential Energy
Kinetic Energy
Kinetic Energy
Electrical Energy
stored in the water
in the water
in the turbines and the generator
in the cables.

64. in the turbines and the generator
Tidal Power
Gravitational Potential Energy
Kinetic Energy
Kinetic Energy
Electrical Energy
stored in the water
in the water
in the turbines and the generator
in the cables.

65. in the turbines and the generator
Wave Power
Kinetic Energy
Kinetic Energy
Electrical Energy
in the water
in the turbines and the generator
in the cables.

66. in the turbines and the generator
Geothermal Power
Heat Energy
Heat Energy
Kinetic Energy
Kinetic Energy
Electrical Energy
in the ground
in the water
in the water
in the turbines and the generator
in the cables.

67. in the turbines and the generator
Biomass
Chemical Potential Energy
Heat Energy
Kinetic Energy
Kinetic Energy
Electrical Energy
stored in the biomass
in the water.
in the water
in the turbines and the generator
in the cables.

68. in the turbines and the generator
Nuclear
Chemical Potential Energy
Heat Energy
Kinetic Energy
Kinetic Energy
Electrical Energy
stored in the fuel
in the water
in the water
in the turbines and the generator
in the cables.

69. Energy Resources Chart
Create a “Top Ten” of energy resources.
Coal
Gas
Nuclear
Hydroelectric
Wind
Biomass
Solar
Geothermal
Wave
Tidal

70. Energy Resources Poster
By the end of the lesson create a poster showing:
The energy transfers.
The advantages.
The disadvantages.
A rating out of 10 for how useful it is for the UK.
A rough diagram showing how it works.

71. Objectives Explain how heat is transferred by conduction.
Explain why free electrons make metals better conductors.

72. Heat Energy
Thermos Flasks

73. Conduction

74. Conduction

75. Conduction Heat transfers by conduction.
The energy is passed on by particle vibrations.
As particles are closer together in solids they are better at passing on the energy.
Metals contain free electrons.
These electrons can move from atom to atom, passing on the energy quickly.

76. Conduction Conduction is the transfer of ____ by ________.
When you heat a substance the _____ have more _______ energy.
Atoms vibrate and ‘pass on’ ______.
_____ are better __________ of heat due to free _______.
Words: vibrations conductors heat kinetic electrons atoms Metals energy

77. Objectives
Explain how heat is transferred by convection.

78. Density How much mass there is in a certain amount of space. Heat
Heating &
Expansion.
Same Mass,
More Space.
Less
Dense.

79. Convection Heated liquid rises up.
Colder water moves in to replace it.
This sets up a convection current.

80. Convection
Convection is the transfer of heat through _____, i.e. _______ & ______.
When heated they ______ due to larger particle ________. This makes the hotter fluid less _____.
The less dense fluid _______ and cooler fluid ____ to take its place.
Words: expand falls liquids vibrations gases dense fluids rises up

81. Conduction & Convection
Similarities
Differences

82. Convection
How does this heater heat the entire room?

83. Convection
How do fridges keep cool?

84. Objectives
Explain how heat is transferred by conduction, convection, and radiation.
Explain how heat loss can be minimised.

86. Radiation

87. Using Radiation Make Three Lists: How black surfaces are used.
How silver surfaces are used.
How we make use of objects giving out different amounts of radiation, e.g. a house.

88. Radiation Dark, matt colours absorb and emit thermal radiation.
Light, shiny surfaces reflect thermal radiation.
Infrared Challenge

89. Radiation
Radiation is the transfer of ____ as _____________ ______. Thermal radiation is also known as ________ radiation.
______ surfaces emit more radiation that ______ surfaces.
____, _____ surfaces are the best emitters and _________ of radiation.
_____ _____/______ surfaces are the best _________.
Words: infrared black hotter cooler
silver heat waves shiny white
absorbers reflectors electromagnetic dull

90. House Insulation
Double Glazing
Glass
Air Space/
Vacuum

91. House Insulation
Loft Insulation
Fibre Glass
Pockets of
Trapped Air

92. Cavity (space) between walls.
House Insulation
Cavity Wall Insulation
Cavity (space) between walls.
Insulation

93. Gaps around doors/windows.
House Insulation
Draught Proofing
Gaps around doors/windows.

94. Chapter 13 Questions
a) Torch

95. Chapter 13 Questions
b) Lighting a Candle

96. Chapter 13 Questions
c) Rubbing Hands Together

97. Chapter 13 Questions
d) Bouncing on a trampoline

98. Chapter 13 Questions 1200 J 3600 J 2400 J Electrical Energy
a) Electric Lamp 
Light
Energy
1200 J 
1.2 cm
3600 J 
3.6 cm 
Electrical
Energy 
Heat
Energy
2.4 cm
2400 J 

99. Chapter 13 Questions 8 MJ 6 MJ 1.2 MJ Electrical Energy
b) Washing Machine 
Kinetic
Energy
1.2 cm 
1.2 MJ  
8 MJ
8 cm
6 MJ
Heat Energy
6 cm
Electrical
Energy  
Wasted Heat & Sound
Energy
0.8 MJ 
0.8 cm 

100. 10 kJ Heat Energy in Kettle 40 kJ Wasted Heat & Sound Energy
Chapter 13 Questions
a) Kettle 
0.1 cm
10 kJ Heat Energy in Kettle 
400 kJ 
350 kJ
4 cm
Heat Energy
in Water
3.5 cm
Electrical
Energy   
0.4 cm
40 kJ Wasted Heat & Sound Energy

101. Chapter 13 Questions b)

102. Chapter 13 Questions

103. Chapter 14 Questions