THE GRAVITATIONAL ATTRACTION DUE TO AN
EXTENDED BODY
Newton’s law of gravitation is really a statement about the force between two point
particles: objects that are very small in comparison with the distance between
them. However, Newton also proved that a uniform sphere attracts another body as
if all of the sphere’s mass were concentrated at its center, so we can also apply
Newton’s law of gravitation to objects that are not small, relative to the distance
between them.