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The Energy Family

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 along 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 seen the geysers 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 converting electromagnetic energy into 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 radio waves. 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 transferred 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 be converted 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 change a light bulb just after it burned out? What you 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

solarflashlightimage Another example of conversion of energy would be a solar panel. A solar panel captures light energy from the sun and converts it to electricity. You can then use this electricity to power a flashlight or radio.
 

toasterimageThink 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 tasks. 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 your 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 your answers from the following choices: chemical energy, electromagnetic energy, electrical energy, thermal energy, and mechanical energy.)

  1. What type of energy comes from the batteries used in the flashlight?
  2. What type of energy is given off when a flashlight is turned on?
  3. What type of energy is felt after the flashlight has been on for several minutes?
  4. Imagine yourself riding a rollercoaster ride. What forms of energy conversation are exhibited during the ride?
Check your answers by highlighting the following box.
1. chemical energy, 2. electromagnetic energy, 3. thermal energy, 4. mechanical energy

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Updated October 24, 2008 by: Glen Westbroek

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