A 55 kg person stands on a scale in an elevator that accelerates downward at 3 m/s2.

Question

a) What is the scale reading?
N

b) What is the person's weight?
N

Answer 1

a. F= ma = 55 * 3 = 165 N.

b. a + g = -3 m/s^2,
a - 9.8 = -3,
a = -3 + 9.8 = 6.8 m/s^2.

F = ma = 55 kg * 6.8 m/s^2 = 374 N =
The person's wt.