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[edit] What are Work and Energy?

During this chapter you will discover that work and energy are very closely related: We consider the energy of an object as its capacity to do work and doing work as the process of transferring energy from one object or form to another. In other words,

• an object with lots of energy can do lots of work.
• when work is done, energy is lost by the object doing work and gained by the object on which the work is done.

Lifting objects or throwing them requires that you do work on them. Even making electricity flow requires that something does work. Something must have energy and transfer it through doing work to make things happen.