A planet of mass M has two moons, one with mass m1 and the other with mass m2. If m1 is less than m2, what can we say about the gravitational force between the each moon and the planet?

Question

They are the same.
Force for m1 is smaller than m2.
Insufficient information.
Force for m1 is larger than m2.

Answer 1

If the planet's mass is P, then if both moons are the same distance away,
F1 = GPm1/r^2
F2 = GPm2/r^2
m1 < m2, so F1 < F2

However, it is unlikely that both moons will be in the same orbit, so now you need to consider the values of r.