A student stands on a bathroom scale in an elevator at rest on the 64th floor of a building. The scale reads 828 N.
(a) As the elevator moves up, the scale reading increases to 919 N. Find the acceleration of the elevator.
(b) As the elevator approaches the 74th floor, the scale reading drops to 782 N. What is the acceleration of the elevator?
(c) Using your results from parts a and b, select which change in velocity, starting or stopping, takes the longer time. Explain.
The Attempt at a Solution
I've done all of these problems twice and I can't figure out the solution. I thought you would just find the average acceleration but I guess not.