Universal gravitation

Learning objectives

To understand how to place an object in orbit.
To show that circular motion is a special case of an elliptical orbit.

This is an animated version of Newton's famous drawing illustrating the concept of free fall. Both free fall and the launch of an object into orbit are governed by the same theory of gravity.

Use the '+' and '-' buttons to observe different cases, ranging from vertical free fall (with an initial velocity of zero) to escape velocity (11.3 km/s from the ground).

Frictional effects have been neglected, so only the force of gravity is acting.