Answer to Question #184341 in Astronomy | Astrophysics for Nicole

Question

The forces exerted between the Earth and the Moon...

A) are equal in magnitude and opposite in direction, since they are action reaction pairs.

(B) are larger on the Moon because the Earth is more massive and exerts a larger force

(C)are smaller on the Moon since the Earth is more massive and exerts a larger force

(D) are equal in magnitude and in the same direction, since they are action reaction pairs.

Answer 1

According to the Newton's law of gravity,

$\displaystyle F = \frac{GMm}{r^2}$

The body of mass M experience the attraction of body with the mass m, but in the same way m experience the attraction of M (according to the third Newton's law). The magnitude of the force is the same for both bodies and can be found from the formula above. The directions of the forces are opposite. So the answer is A).

Answer: A)