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A 60kg man stands on a spring scales in ...

A 60kg man stands on a spring scales in a lift. At some instant. He finds that the scale reading has changed from 60kg to 50 kg for a while and then comes back to original mark. What should be concluded?

A

The lift was in constant motion upwards

B

The lift was in constant motion downwards

C

The lift while in constant motion upwards, is stopped suddenly

D

The lift while in constant motion downwards, is suddenly stopped

Text Solution

Verified by Experts

The correct Answer is:
C
For upward acceleration apparent weight = m(g+a)
If lift suddenly stops during motion then apparent weight = m(g-a) because instead of acceleration, we will consider retardation.
If the problems it is given that scale initially was 60 kg and due to sudden jerk reading decreasing and finally comes back to the original mark i.e. 60 kg.
So,we can conclude that lift was moving upward with constant speed and suddenly stops.
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