Question

A box is lowered using a rope. If the acceleration of the box, is 2.5 m/s2 (downward) and the tension in the rope is 31 N, what is the mass of the box (in kg)?

Answer 1

F= ma
31-mg = m(-2.5m/s2)
31= mg-2.5 m
31 = m*(9.8m/s2 -2.5 m/s2)
31 = 7.3 m
m = 31/7.3
m = 4.25 kg