Energy Conversion and Conservation
Conversions Between Forms of Energy
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Energy Conversion: Is a change
from one form of energy to another.
Most forms of energy can be
converted into other forms.
Ex: Lamp and clock convert electrical energy into
electromagnetic.
A water heater converts chemical energy in natural
gas to thermal energy.
Energy Conversions
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Body converts chemical energy in
the food you eat to mechanical
energy you need to move your
muscles. It is also changed into
thermal energy your body needs to
maintain its temperature.
A toaster converts electrical energy
to thermal energy.
Series of Energy Conversions
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Strike a match:
Mechanical energy used to
scratch the match is
converted to thermal
energy. The thermal
energy causes the match
to release stored chemical
energy, which is converted
to thermal energy and to
energy you see as light.
Example of Series:
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Car engine: Electrical energy
produces a hot spark. The thermal
energy of the spark releases
chemical energy in the fuel. When
the fuel burns, this chemical energy
in turn becomes thermal energy.
Thermal energy is converted to
mechanical energy used to move
the car, and to electrical energy that
produces more sparks.
Law of Conservation
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States that when one form of
energy is converted to another, no
energy is destroyed in the process.
Energy cannot be created or
destroyed.
Conserving Energy
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Means saving
energy, or not
wasting it.
This means that we
should not waste
fuels, such as
gasoline, or our
resources will be
used up quickly.
Review
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What is an energy conversion?
A change from one form of energy
to another or an energy
transformation.
Review - 2
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State the law of conservation of
energy in your own words.
The total energy before a process is
the same as the total energy after.
Review - 3
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Describe the energy conversions that occur when
a ball is dropped and bounces back up. Why do
you think the ball bounces a little lower each
time?
As it falls, potential energy changes to kinetic
energy. As it bounces back up, kinetic energy is
converted to potential energy. The ball does not
bounce a high because some energy escapes as
thermal energy or sound when the ball hits the
ground.
Formation of Fossil Fuel
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Fuel: A material that stores
chemical potential energy.
Fossil Fuels: Coal, petroleum, and
natural gas.
Fossil fuels contain energy that
came from the sun
Use of Fossil Fuel
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Fossil fuels can be burned to release
the potential energy stored millions
of years ago.
Energy Conversions – Sun to Toaster
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1) The sun converts nuclear energy to electromagnetic
energy.
2) Ancient plants and animals convert electromagnetic
energy from the sun to stored chemical energy.
3) Remains of plants and animals become coal over
millions of years.
4) Stored chemical energy in coal is converted to thermal
energy when the coal is burned to make steam.
5) Thermal energy is converted to mechanical energy as
turbines are turned by steam.
6) Mechanical energy is converted to electrical energy as
turbines turn electric generators.
7 Electrical energy is converted to thermal energy in your
toaster