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A cord of negligible mass is wound round...

A cord of negligible mass is wound round the rin of a flywheel of mass 20 kg and radius 20 cm. A steady pull of 25 N is applied on the cord. The work done by the pull when 2 m of the cord is unwound is a) 20 J b) 25 J c) 45 J d) 50 J

A

20 J

B

25 J

C

45 J

D

50 J

Text Solution

Verified by Experts

The correct Answer is:
d
Work done by the pull unwinding 2m of the cord,
W`=25 N xx 2 m= 50 J`
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