A lamp hangs vertically from a cord in a descending elevator.
The elevator has a deceleration of 2.4 m/s2 before coming to a stop.
(a) If the tension in the cord is 89 N, what is the mass of the lamp?
(b) What is tension in the cord when the elevator ascends (goes up) with an upward acceleration of 2.4 m/s2?