Posted by Elisabeth on Friday, September 9, 2011 at 7:01pm.
A 44.0 kg man stands on a bathroom scale in an elevator. Starting from rest, the elevator ascends, attaining its maximum speed of 1.90 m/s in 1.19 s. It travels with this constant speed in the upward direction for the next 7.60 s. The elevator then slows down (undergoes a uniform acceleration in the negative y direction) for 2.15 s and comes to rest. What does the bathroom scale register before the elevator starts to move? Answer in units of N. (Hint: What is the velocity of the elevator then?)

Physics  Natalie, Sunday, October 9, 2011 at 11:25am
The elevator has not moved yet, so the normal force and the force of the man's weight are equal. The answer is 431.2 N
n  mg = ma
n  mg = 0, so
n = mg
n = 44.0*9.8
n = 431.2