Friction - A force that is involved wherever two substances move against each other. The rubbing of the two substances causes them to pull at each other, and thus absorbing some of the force applied to the substance.

Newton's First Law of Motion - States that "An object in motion will stay in motion unless acted upon by an outside force."

Centrifugal Force - The component of force acting on a body in curvilinear motion that is directed toward the center of curvature or axis of rotation. Centripetal force is necessary for an object to move with circular motion.

Power - The rate at which work is done, expressed as the amount of work per unit time and commonly measured in units such as the watt and horsepower.

Work - The transfer of energy from one physical system to another, especially the transfer of energy to a body by the application of a force that moves the body in the direction of the force. It is calculated as the product of the force and the distance through which the body moves and is expressed in joules, ergs, and foot-pounds.

Gravity - The natural force of attraction exerted by a celestial body, such as Earth, upon objects at or near its surface, tending to draw them toward the center of the body. Earth's gravity is 9.80 m/s/s.

When you are done reading the Flares and Windmills pages you can take a test to see just how much you know about your Mills and Flares.