A heavy rock and a light rock in free fall have the same acceleration because the
A)force due to gravity is the same on each.
B)air resistance is always zero in free fall.
C)inertia of each is the same.
D)ratio of force to mass is the same.
E)none of the above

Question

Quizplus · Accepted Answer

The acceleration of an object in free fall is determined by the ratio of the gravitational force acting on it to its mass. According to Newton's second law, acceleration is the result of force divided by mass (a = F/m). Since the force due to gravity is proportional to the mass of the object (F = mg), when you divide the gravitational force by the mass of the object, the mass cancels out, leaving the acceleration due to gravity (g) as a constant for all objects, regardless of their mass. This is why both a heavy rock and a light rock have the same acceleration in free fall, assuming air resistance is negligible.

A Heavy Rock and a Light Rock in Free Fall