Two Comets Are Found at the Same Distance from the Sun

Multiple Choice

Two comets are found at the same distance from the Sun. However, one comet is three times as massive as the other. According to Newton's Universal Law of Gravitation the force of gravity exerted by the Sun on the more massive comet is

A) one-ninth the size of the force exerted on the less massive comet
B) one-third the size of the force exerted on the less massive comet
C) the same size as the force exerted on the less massive comet
D) three times as large as the force exerted on the less massive comet