The amount of force needed to sustain motion of a rock in outer space is
A)a force equal to its weight.
B)a force less than its weight if friction is absent.
C)none of these

Question

Quizplus · Accepted Answer

In outer space, once an object is in motion, no force is needed to sustain its motion due to the absence of friction and other forces. This is in accordance with Newton's first law of motion.

The Amount of Force Needed to Sustain Motion of a Rock