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

It does, but it’s only noticeable if both objects are massive.

Force = Gravitational constant * mass1 * mass2 / radius^2.

That force works both ways. The Earth pulls a hammer at the same acceleration as a feather, but the earth is accelerated faster towards the hammer than to the feather. It’s just that a force equivalent to the weight of a hammer is still negligible when compared to the mass of the Earth, even if it’s hundreds of times higher than the feather.