Centripetal force and gravitation

Learn about centripetal acceleration and centripetal force. Also, learn about the universal law of gravitation and gravitational orbits.
See how you score on these 7 practice questions

Why do things move in circles? Seriously. Why does *anything* ever move in a circle (straight lines seem much more natural)? Is something moving in a circle at a constant speed accelerating? If so, in what direction? This tutorial will help you get your mind around this super-fun topic.

Why are you sticking to your chair (ignoring the spilled glue)? Why does the earth orbit the sun (or does it)? How high could I throw my dog on the moon? Gravitation defines our everyday life and the structure of the universe. This tutorial will introduce it to you in the Newtonian sense.