If you were making up a children's story, you might consider the story
of Mom and Pop Energy! These two parents had six little energies. The
family was considered by their neighbors to be the movers and shakers
of the neighborhood. Their children were: Mechanical, Thermal, Chemical,
the twins- Electrical and Electromagnetic, and of course the baby- Nuclear.
The family always got long with each other. In fact, they loved to
share with each other. As with all families, there were rules to follow.
These rules were very important and were always obeyed. The first and
most important rule is called the Law of Conservation.
That simply means that energy cannot be created nor destroyed. Energy
can change its form, but the amount of energy will remain the same before
and after each transfer.
Mechanical
energy loves to move. It is the "energy" that deals with motion. Mechanical
energy has two great friends. They are called - kinetic and potential
energy.
The
mechanical energy of a waterfall can be converted to electromagnetic
energy in a generator. Generators convert other types of mechanical
energy into electromagnetic energy. Another example is the bicycle generators
that turn with the bicycle tires and cause the light to turn on. Due
to changes in the speed of the bicycle, these lights often change from
bright to dim!
Thermal energy is a real hot-head. Here, energy is made by molecules
within the matter that move so fast that heat is generated. Thermal
energy also has a friend called geothermal. Geothermal energy is used
to generate electricity for towns and cities located above super-heated
ground water. Perhaps you have visited Yellowstone National Park and
see the geysers that are there. Some like Old Faithful are large and
famous while others are smaller and less noticed (like shown in the
QuickTime movie below.)
Chemical
Energy loves to store things. Chemical energy is stored in chemical
compounds by chemical bonds. Eating foods such as fat, carbohydrates
and other compounds releases energy into our bodies giving us energy.
Photosynthesis is an example of chemical energy. Another example of
chemical energy is a bomb used by the military. Energy is stored in
these chemicals but when more energy is added, stored energy is released.
Electrical energy is a shock. It is the energy of electrical charges.
Moving electrical charges create electricity so this type of energy
is made in the atomic structure.

Electrical energy and electromagnetic energy are closely related.
Electromagnetic energy travels in waves. This energy has some
electrical properties and some magnetic properties. It is produced
by the sun and other light giving forms. Other forms of this energy
include radiation, microwaves, and radiowaves. While you cannot
see this form of energy, you are able to prove its presence. Turn
on a radio and listen to the sounds that are transfered through
the atmosphere using radio waves. Put water in a glass container
in the microwave, turn it on and observe the water heat up. Stay
outside too long in the sunshine and your skin gets sunburned! |
The baby of the energy family packs a big bang. Nuclear energy is stored
in atoms and when released during a nuclear reaction gives off a great
amount of energy. While this form of energy was used during World War
II, since that time humans have not used it as a weapon of war. We do,
however, see this form of energy used to create power in some power
plants. In these locations, nuclear energy must be controlled to prevent
problems.
Energy can convert from one form to another. This is called "conversion
of energy." Consider this idea as you read the following.
Have you ever touched a light bulb when it was on? Perhaps you
tried to hang change a light bulb just after it burnt out. What
you have discovered is the conversion process of energy? When you
turn on a light, not all of the electricity is converted to light
energy. Some of the energy is converted to heat. Although some energy
is changed to heat and does not help do the work, the energy is
not lost. In fact, energy is never lost; it is only converted from
one form to another. You proved there is heat energy when you touched
the light bulb.
An other example of conversion of energy would be a solar panel.
A solar panel captures light energy from the sun and convert it
to electricity. You can then use this electicity to power a flashlight
or radio. |
| Think
about the many energy conversions it takes to make a piece of
toast. This simple action helps you to realize how often
energy conversions occur on many simple task. Make a list of all
the ways that energy is converted as you read the following paragraph.
Chemical energy stored in coal is released as heat and light
energy when the coal is burned. The heat energy is used to produce
steam and is changed into mechanical energy in a generator. The
generator converts mechanical energy into electric energy that
travels through power lines into your home. When you use your
toaster, that electric energy is again changed into heat energy.
Then when you eat the toast, chemical energy is involved because
you body breaks down chemical bonds to give you energy to run.
None of the energy is lost, only transferred. How many did you
count? |
Analysis: (Choose from the following choices: chemical
energy, electromagnetic energy, electrical energy, thermal energy, and
mechanical energy.)