Why does the mass of planets affect the gravity on their surface but the mass of objects doesn’t affect how fast they fall.

Question

Why does the mass of both objects not factor? Did I misunderstand the reason for differing gravity on other planets?

In: Physics

Answer 1

The force of gravity does depend on the mass of the two things, like you said. Earth’s gravity does pull harder on a 10 lb steel ball than a 1 lb wood ball.

**But it also takes more force to accelerate a heavier object!**

These two things cancel out. Gravity pulls the steel ball harder, but it takes more pull to accelerate the heavy ball. The way the math works out, these two factors always exactly cancel out so that the resulting falling speed is always the same, and doesn’t depend on the weight of the dropped object (ignoring air resistance).