What is energy? We need energy to make things work. Energy is the ability to work.

What is energy?

•We need energy to make things work.

•Energy is the ability to work.

Different forms of energy * Heat energy * Potential energy

*Kinetic energy * Electrical energy

* Light energy * Sound energy

*Chemical energy

Energy conversion When we turn on the light… Electrical light energy & heat energy.

When we turn on the radio…Electrical energy sound energy.

When we wind up a toy car…Kinetic energy potential energy

When we run…Chemical energy kinetic energy

Clear:•For the past

•Burn coal

•Dirty

•Now

•Use electricity

•More clean

Convenient:For the past:Buy oil Put it into the oil lamplight a match Waitlight comes out

Now:Put the plugs into thesocketPress the switchimmediatelylight

Pollution from electricity

•Air pollution:•Sulphur dioxid

e-----acid rain---kill the trees

•carbon dioxide----Greenhouse effect

The amount of that energy people use

• The diagram shows us, we had use a lot of energy.

• Once some kind of energy are used up, the energy they contain will gone forever.

• So we have to save energy.

Annual energy consumption per person, billions of joules

0 100 200 300 400

India

Brazil

China

Japan

Britain

Germany

Russia

Canda

U.S.

Summary

• Energy is very important in our daily lives. When we product some kind of energy, we will make some pollution.

• If we use the energy misapply, the energy will use up one day.

• So we have to save energy and save our Earth.

Group membersChan Shui Chi Lo Kwun Yi

Cheung Ka Yan Tong Sin Yi

Leung Wai Ching Wong Nap Pui

Lam Tsz Ling

~The End~