Two students simultaneously drop a ball and a ball from the same height near Earth’s…
PHYSICS · Single correct · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
Two students simultaneously drop a 1kg ball and a 5kg ball from the same height near Earth’s surface, neglecting air resistance. Which statement best describes the gravitational interaction forces during the fall?
(a) Earth exerts the same gravitational force on both balls because the acceleration due to gravity is constant, so each ball exerts the same force back on Earth.
(b) Earth exerts a larger gravitational force on the 5kg ball, but that ball exerts a smaller force on Earth because Earth’s mass is so large.
(c) Earth exerts a larger gravitational force on the 5kg ball, and that ball exerts an equal–magnitude force back on Earth; the forces for the 1kg ball are smaller but still equal in its pair.
(d) Each ball exerts a negligible gravitational force on Earth, so only Earth’s forces on the balls are significant.