energy

Introduction

CE5

Relations between potential energy (PE) and kinetic energy (KE) for a swinging pendulum

energy, in physics, the ability or capacity to do work or to produce change. Forms of energy include heat, light, sound, electricity, and chemical energy. Energy and work are measured in the same units—foot-pounds, joules, ergs, or some other, depending on the system of measurement being used. When a force acts on a body, the work performed (and the energy expended) is the product of the force and the distance over which it is exerted.

Sections in this article:

Introduction
Conversion and Conservation of Energy
Potential and Kinetic Energy

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