Galileo used an inclined plane to determine the rate of acceleration due to Earth's gravity. In one experiment, he changed the pitch of the plane, but not its height.

How gravity causes a perfectly spherical ball to roll down an inclined plane is part of the elementary school physics canon. But the world is messier than a textbook. Scientists in the Harvard John A.

and he rolled bronze balls down inclined planes a thousand ways to derive the rate of acceleration in free fall. Through such pursuits, Galileo discovered and described phenomena that generations ...