What is energy We need energy to

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 • Now • Burn coal • Use electricity • Dirty • More clean

Convenient: Now: Put the plugs into the socket Press the switch immediately light For the past: Buy oil Put it into the oil lamp light a match Wait light comes out

Pollution from electricity • Air pollution: • Sulphur dioxide----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.

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 members Chan Shui Chi Lo Kwun Yi Cheung Ka Yan Tong Sin Yi Leung Wai Ching Wong Nap Pui Lam Tsz Ling ~The End~