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When a block of mass M is suspended by a...

When a block of mass M is suspended by a long wire of length L, the length of the wire becomes `(L +l)`. The elastic potential energy stored in the extended wire is:

A

`(1)/(2) MgL`

B

Mgl

C

MgL

D

`(1)/(2) Mgl`

Text Solution

Verified by Experts

The correct Answer is:
D

Elastic potential energy
`=(1)/(2) xx` (force) `xx` (increase in length)
`=(1)/(2) xx mg xx (L + l -L)`
`=(1)/(2) mgl`
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  • When 1 N force is applied increase in length of the spring is 1 cm . Find elastic potential energy stored during this in it .

    A
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