The weight of a human in an elevator?

Question

A 75kg person stands in an elevator. what force does the floor exert on the person when the elevator
(1) starts moving upward with an acceleration of 1.5 m/sec^2?
(2) moves upward with a constant speed of 2.0 m/sec?
(3) starts accelerating downward at 1.5 m/sec^2?
(b) If the person were standing on a bathroom (spring) scale during the ride, what readings would the scale have under conditions (1), (2), and (3) above.
(c) It is sometimes said that the "apparent weight" changes when the elevator acclerates. what could this mean? Does the weight really change?

Answer 1

1. f = m*(g+1.5) N
2. f = m*g N
3. f = m*(g-1.5) N
b. If scale reads in N the values will be as given in (1) - (3), if in kg, the given values divided by g.
c. It really changes, since weight is a force and the force changes.