Beginning of Essay
Have you ever wondered how a jet aircraft lifts its tremendous weight off the ground, or what gives a runner the stamina to reach the finish line in a race? In order to answer all these questions we must talk about the transformation of one sort of energy into an ....

Middle of Essay
.... contains energy-giving substances that our bodies can store until we need this energy to use our muscles. When we do use our muscles within us, we may not always be sure that heat is given off. Our bodies do not burst into flames but the perspiration on our skin is a clue to what is happening. The movement of the windsurfer has a different explanation. The windsurfer is propelled along by a sail which collects from the winds that sweep along the water. This energy has been produced by the sun which warms the earth's surface and sets the air above in motion. The sun's heat comes to the earth as a form of radiant energy. When the heat reaches t ....