Question

A 65.0 kg person rides in elevator while standing on a scale. The elevator is traveling upward but slowing down at a rate of 2.00 m/s2 . The reading on the scale is closes to

Answer 1

Since the elevator is going up and slowing down, its acceleration is directed downwards.

As elevator is accelerating, the person inside it will feel a pseudo force opposite to the direction of the acceleration of elevator.

Let the normal reaction on the person by the scale be N, his mass be m and acceleration of the elevator be a.
From force balance equation on the person

   N + ma = mg   where 'ma' is pseudo force on the person

N = mg - ma = m(g - a)

   N = 65(10 - 2) = 520

Scale will read 520N.