The common meaning of the word work refers to the accomplishment of a task. When work is done, energy will be expanded. Hence work and energy are very closely related.

A student performs a certain amount of work during the day, and he or she will become tired. He or she must obtain rest and food in order to continue to be able to work. We know that rest along is not sufficient to keep a person going; thus the food must work as fuel to supply the necessary energy.

The technical meaning of the word work is actually quite different from the common meaning. A student standing at rest and holding the several book is doing no work, although he ot she might fell tired after a while. Technically speaking, work is accomplished only when the force is acting through a distance.

Energy is sometimes called stored work, and our mastery of energy has produced today's high tech civilization. From the control of fire to the control of nuclear energy, we have improved our standard of living through our ability to use and control the flow of energy. Energy takes many forms, such a mechanical, heat and many many more. These forms, as we shall learn, are classified in the more general categories like kinetic and potential energy.

Our main source of energy is the Sun, which radiates into the space each day an enormous amount of radiant energy, and only a small portion is received by the Earth. Radiant energy supports kinds of life on our planet and provides us with the means for making nature work for the Earth's inhabitants.

Bookmark This Page