A 60 kg man stands on a spring scale in the lift. At some instant he finds, scale reading has changed from 60 kg to 50 kg for a while and then comes back to the original mark. What should we conclude
The lift while in constant motion upwards, is stopped suddenly
For retarding motion of a lift R = m(g + a) for downward motion
R = m(g – a) for upward motion
Since the weight of the body decrease for a while and then comes back to original value it means the lift was moving upward and stops suddenly.
Note: Generally we use R = m(g + a) for downward motion
R = m(g – a) for upward motion
Here a = acceleration, but for the given problem a = retardation