A planet is orbiting a star. Which of the following statements is true for the acceleration and gravitational forces experienced by the star and the planet?
A)The force on the star is much smaller than the force on the planet, but the accelerations are about equal.
B)The acceleration of the planet is much more than the acceleration of the star, but the force on the star is the same but opposite the force on the planet.
C)The acceleration of the planet is much more than the acceleration of the star, and the force on the planet is much more than the force on the star.

Question

Quizplus · Accepted Answer

According to Newton's third law of motion, for every action, there is an equal and opposite reaction. In the case of a planet orbiting a star, the planet experiences a gravitational force towards the star, and in return, the star experiences a gravitational force towards the planet. Both the star and the planet experience the same magnitude of force but in opposite directions.

However, the acceleration experienced by each object is different. The acceleration of the planet towards the star is much more significant than the acceleration of the star towards the planet because the planet has much less mass than the star. Thus, the force on the star is the same but opposite to the force on the planet, but the acceleration of the planet is much more significant than the acceleration of the star. Hence, choice B is correct.

A Planet Is Orbiting a Star