What is energy? We need energy to make things work. Energy is the ability to work.
-
Upload
randell-underwood -
Category
Documents
-
view
221 -
download
2
Transcript of 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
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.