Question

A woman standing on a scale in an elevator notices that the scale reads 20 N greater than her normal weight. Which type of movement on the part of the elevator could cause this greater than normal reading?

a. moving downward at constant speed

b. accelerating downward

c. accelerating upward

d. moving upward at constant speed

*NOTE* DO NOT GUESS ON THIS QUESTION.

Answer 1

C. Accelerating upward

Has to do with Newtons 2nd law of motion.
F=MxA. Mass times acceleration
So acceleration upwards the scale is pushing back on your normal weight plus your mass and the acceleration rate of the elevator car.

The opposite occurs when descending.

If at a constant speed/velocity, equilibrium occurs and weight exerted by ones body stays the same.