This presentation contains basic knowledge for the understanding of the concept of energy. It was mainly prepared for a Form 3 class whereby the forms of energy have already been elaborated in lower levels.

1. Jouman Bibi Nousrat
Energy

2. Learning objectives
At the end of the lesson, you should be able to:
1. Recall the definition for energy and state its unit.
2. Iist the different forms of energy and their sources.
3. Perform simple calculations for kinetic (K.E = ½ mv2 )
and potential energy( P.E = mgh) using the formulae.
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3. Prior knowledge
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6. Different forms of energy
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7. ENERGY
Electrical
Energy
Heat
Energy
Light
Energy
Kinetic (Motion)
Energy
Sound
Energy
Chemical
Energy
Potential
Energy

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9. memonic
He Keeps Eating Lightly Salted
Potato Chips
Heat Kinetic Electrical
Light Sound Potential Chemical
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10. Worksheet
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11. 1. (a) What do you understand by energy? State its unit.
(b) Energy can be classified into two groups; namely stored energy and ………….. .
1. (a) Light energy is produced by luminous bodies like the sun,................, and
…………….
(b) …………., ………….. And batteries are sources of chemical energy.
(c) …………….. Energy can be produced by generators, cells or batteries. It is a form
of energy that can be converted from one form to another.
(d) …………….. Is produced by vibrating objects.
(e) A hot bowl of soup possesses ……………… energy.
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12. 3. Match the following source of energy with the forms of energy obtained
from them.
Sources forms
Sun
Gravitational potential
Fossil fuel Chemical
A boy running Solar
A cyclist on the top of a hill Kinetic
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13. Calculations for kinetic and potential energy
1. A stone of mass 20 kg is released from a height of 5 m above the ground.
Calculate the gravitational potential energy of the stone at the point of
release. Take g = 10 m/s2.
2. From the Form 3 textbook pg 76 no 1:
Calculate the kinetic energy of a body of mass 10 kg moving at 5 m/s.
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14. Law of conservation of energy
Energy can neither be created nor
destroyed. Energy can be transformed
from one form to the other.
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15. Energy Transfer
Energy
Form =
Where to Where?
icehands
HEAT

16. Energy Transfer
Energy
Form =
Where to Where?
appliance
(TV, computer, etc)
outlet
ELECTRICAL

17. Energy Transfer
Energy
Form =
Where to Where?
CHEMICAL
Fly
(food)
Frog
(growth)

18. Energy Can Be Transformed
Electrical energy is transferred
from the wall socket to the
computer.
Electrical energy is transformed
to sound and light energy when
the computer is turned on.
Electrical energy is transformed
to heat energy when the
computer stays on.

19. Summary of the lesson
Energy
Forms of energy
Formulae for Kinetic energy and Potential energy
Law of conservation of energy.
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