# FHSST Physics/Work and Energy/Summary

Work and Energy The Free High School Science Texts: A Textbook for High School Students Studying Physics Main Page - << Previous Chapter (Momentum) - Next Chapter (Collisions and Explosions) >> Definition - Work - Energy - Mechanical Energy and Energy Conservation - Important Quantities, Equations, and Concepts - Sources

# Summary of Important Quantities, Equations and Concepts

 Units Quantity Symbol Unit S.I. Units Direction Work W J N.m or${\displaystyle kg.m^{2}.s^{-2}}$ -- Kinetic Energy EK J N.m or${\displaystyle kg.m^{2}.s^{-2}}$ -- Potential Energy EP J N.m or${\displaystyle kg.m^{2}.s^{-2}}$ -- Mechanical Energy U J N.m or${\displaystyle kg.m^{2}.s^{-2}}$ --

Principle of Conservation of Energy: Energy is never created nor destroyed, but merely transformed from one form to another.

Conservation of Mechanical Energy: In the absence of friction, the total mechanical energy of an object is conserved.