A classical mechanics problem by Edward Gleason
A ball is dropped from the edge of a cliff 100 meters from the ground. At the same time, a car that is 100 meters from the cliff base starts from rest toward the cliff. How fast will the car have to accelerate toward the cliff so that it arrives at the cliff base at the same moment the ball reaches the ground? (Ignore air resistance and presume the driver isn't afraid of death.) Use 10 meters per second squared as the surface gravity value.