A student weighing 500. N stands on a spring scale in an elevator. If the scale reads 520. N, the elevator must be
Answer: moving upward at constant speed
The force that the student exerts on the scale is the reaction force of the normal force that the elevator exerts on the student. N = 520. NSince the weight is 500 N which is less than the normal force, the net force of the student is 20 N upwards. Thus, the elevator must be accelerating upward.
