Assume that the reference frame is moving with the person indicated in each of the following situations. In which case is the reference frame noninertial?
A) The person is walking at a constant speed along a straight, horizontal sidewalk.
B) The person is walking at a constant speed along a straight sidewalk that is inclined downward at a slight unchanging angle.
C) The person is riding an elevator upward at constant speed.
D) The person is skydiving and is freefalling not yet having opened her parachute.

Question

Quizplus · Accepted Answer

A noninertial reference frame is one that is accelerating. In the case of skydiving, the person is in freefall, which means they are accelerating due to gravity, making the reference frame noninertial.

Assume That the Reference Frame Is Moving with the Person