A mass is suspended from the roof of a lift (elevator) by means of a spring balance. The lift (elevator) is
moving upwards and the readings of the spring balance are noted as follows:
Speeding up: RU Constant speed: RC Slowing down: RD
Which of the following is a correct relationship between the readings?
(A) RU RC (B) RU = RD (C) RC < RD (D) RC RD