This essay describes the influence that the pendulum had on Galileo's thinking and science. It also discusses the use of a pendulum to measure time. This is a part of The Galileo Project, an extensive web site on the...

Gravity Probe B is the relativity gyroscope experiment being developed by NASA and Stanford University to test two extraordinary, unverified predictions of Albert Einstein's general theory of relativity. The experiment...

This is a collection of online physics courses designed for elementary and middle school teachers. Current courses are on light, electricity and magnetism, temperature, heat, and energy, and force, motion, and energy....

This lesson points out that the motion of objects (velocity or acceleration) is almost never constant, and applies this idea to the motion of a person walking. The discussion covers the energy transfers involved in...

This web page describes inertial and non-inertial frames of reference, the latter being frames where Newton's laws do not hold. The text explains "fictitious forces", the centrifugal force and the Coriolis force, that...