Question

A 80-kg man standing on a scale in an elevator notes that as the elevator rises, the scale reads 828 N. What is the acceleration of the elevator?

Answer 1

F=mg+ (-mg) = may
828N=(the inside eqtn will cancel because it is the weight and the normal force and the man is not moving inside the elevator) = (80kg)ay

828N=(80kg)*ay
828N/80kg=ay
10.35 m/s^2

Answer 2

Set up the equation like this:

1) ma = F in y-direction
2) Plug in given variables
3) (80kg)(?m/s^2) = 828 Newtons
4) Divide both side by 80 to get rid of that number and isolate acceleration.
5) Then you get 10.35 m/s^2 as your answer. (which is acceleration)