Review of Work, Energy and Power

Terms and Formulae

Terms

Conservative force - Any force which conserves mechanical energy, as opposed to a nonconservative force. See statement of conservation of mechanical energy.

Conservative System - A system in which energy is conserved.

Energy - The ability to do work.

Kinetic Energy - The energy of motion.

Nonconservative Force - Any force which does not conserve mechanical energy, as opposed to a conservative force.

Path independence - Property of conservative forces which states that the work done on any path between two given points is the same.

Potential energy - The energy of configuration of a conservative system. For formulae, see Definition of potential energy, gravitational potential energy, and Definition of potential energy given a position-dependent force.

Total mechanical energy - The sum of the kinetic and potential energy of a conservative system. See definition of total mechanical energy.

Work - A force applied over a distance. For formulas, see work done by a constant force parallel to displacement and work done by any constant force, and work done by a position-dependent force.

Joule - The units of work, equivalent to a Newton-meter. Also units of energy.

Power - Work done per unit time. For formulas, see Formula for average power, Definition of instantaneous power, and formula for instantaneous power.

Watt - Unit of power; equal to joule/second.