A close up photo showing a blob of mercury sitting safely inside a glass container. At room temperature this metal is in liquid form, the liquid metal moving around like something out of the movie Terminator 2 Judgment Day. Mercury can...

The Physics Classroom offers this animation depicting the forces acting upon a falling skydiver.

This site from NASA compares free falling motion to falling with air resistance. Discusses Galileo's experiment. Explains why we believe all objects free fall with the same acceleration.

[Free Registration/Login may be required to access all resource tools.] This lesson introduces Polar coordinates.