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An object of mass 10 kg is hanging on a ...

An object of mass 10 kg is hanging on a spring scale which is attached to the roof of a lift. If the lift is in free fall, the reading in the spring scale is

A

98 N

B

zero

C

49 N

D

9.8 N

Text Solution

Verified by Experts

The correct Answer is:
B
If the lift is free fall then a = g.
`thereforeN=m(g-g)=0`
`therefore` The reading will be zero.
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