Energy is the ability to do work and comes in many forms, including potential, kinetic, mechanical, radiant, sound, chemical, heat, and electrical. It can be converted from one form to another but can neither be created nor destroyed. There are two main types of energy sources - renewable sources like solar, wind, and hydroelectric, and nonrenewable sources like coal, natural gas, and petroleum. Conserving energy helps reduce pollution and make nonrenewable resources last longer since much of the energy input is lost as heat during conversion and use.

1. User-Defined Placeholder Text
What is energy?

2. Evidence of energy is everywhere! All you
need to do is look for motion, heat, and light.!
!
Energy is described by these characteristics:!
!
•Energy is the ability to do work.!
•Work is the application of a force through a
distance.!
•A force is a push or a pull that can put matter
in motion.!
•Motion is a change in distance or direction
with time.

3. Two types of Energy
Potential Energy !
• Water behind a dam!
• Car parked on a hill!
• Wound clock spring!
• Gasoline or sugar
Kinetic Energy!
!
•Falling Water!
!
•Car rolls down a hill!
!
•Clock’s hands move!
!
•Energy appears as
movement of the car or
body heat

4. Mechanical!
Radiant!
Sound!
!
Chemical!
Heat!
Electrical!
Nuclear
Remember:!
!
MRS CHEN

5. Energy cannot be created or
destroyed; it can only change form.

6. Natural Gas!
Petroleum or Oil!
Coal!
Solar!
Wind!
Wood!
Hydroelectric!
Ocean Tides!
Geothermal!
Biomass!
Nuclear Fission
Practical Sources of Energy

7. ENERGY
RENEWABLE NONRENEWABLE
Sun! Coal
Water Natural Gas
Wood Petroleum
Wind Nuclear Fission
Biomass
Geothermal
Ocean Tides

8. FYI: How is electricity
made?
Usually a fossil fuel is burned to heat water.
The water turns to steam and forces a
machine called a turbine to turn. The turbine
powers a generator which generates
electricity.!
!
Summary: coal--hot water--steam--turbine--
generator--electricity!
!
A turbine can also be turned by falling water
and wind (wind mills).

9. Why should we not waste
energy?
When energy does work it changes from a
higher form of energy to a lower form. !
!
Example 1: Of the energy needed to light a!
light bulb, only 5% creates light......95% is!
lost as heat.!
Example 2: The chemical energy of!
gasoline is converted to heat in an!
automobile. Only 10% is converted into!
mechanical energy to move the car. The!
rest, 90%, is lost to the environment.

10. How can we save energy?
Conservation!
Recycle!
Reduce !
Reuse
Energy saved is energy
available another day.
Saving energy cuts down
on pollution and helps
our nonrenewable
resources last longer.