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A body of weight mg is hanging on string...

A body of weight mg is hanging on string which extends its length l. The workdone in extending the sring is…….

A

mgl

B

`(mgl)/(2)`

C

2 mgl

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
B
The extension length is `(1)/(2)`
Workdone (W) =Force` xx`Distance
Workdone is extension string =Weight `xx `length extention
=`mgxx(1)/(2), W=(mgl)/(2)`
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