A 90-kg man stands in an elevator that has a downward acceleration of 1.4 m/s². The force exerted by him on the floor is about: A) zero B) 90 N C) 760 N D) 880 N E) 1010 N

Question

Quizplus · Accepted Answer

The force exerted by the man on the floor is the normal force, which is equal to his weight minus the force due to the elevator's acceleration. The weight is 90 kg * 9.8 m/s² = 882 N. The force due to acceleration is 90 kg * 1.4 m/s² = 126 N. Therefore, the normal force is 882 N - 126 N = 756 N, which is approximately 760 N.

A 90-Kg Man Stands in an Elevator That Has a Downward