A man whose mass is 80kg stands on a spring weighing machine inside an elevator.

Question

What is the reading of the weighing machine when:
the elevator is coming to rest with a retardation of 4.0ms

Answer 1

a is in units of m/s^2, not ms
F = m(g+a) = 80(9.81 + 4.0)

Answer 2

is it stopping at the top or stopping at the bottom ?
at bottom stop, g+a
at top stop, g-a

Answer 3

It's actually deceleration not acceleration