Two balls are thrown from the top of a building. One is thrown up and the other is thrown down, both with the same initial speed. Ignoring air resistance, what are their speeds when they hit the street?
A) They are traveling at the same speed.
B) The one thrown down is traveling faster.
C) The one thrown up is traveling faster.
D) It depends on the height of the building.

Question

Quizplus · Accepted Answer

Both balls will have the same speed when they hit the street, regardless of the height of the building. This is because the only force acting on the balls is gravity, which causes them to accelerate at the same rate (9.8 m/s/s) regardless of their initial direction of motion. As a result, the balls will reach the ground with the same speed they started with.

Two Balls Are Thrown from the Top of a Building