Question

A metallic wire of length L metres extends by l metres when stretched by suspending a weight Mg to it. The mechanical energy stored in the wire is

• A.
• B.
• C. $\frac { M g l } { 2 }$
• D. $\frac { M g l } { 4 }$

Answer 1

Answer: (C)

$\frac { M g l } { 2 }$

Answer 2

Elastic potential energy stored in wire $U = \frac { 1 } { 2 } F x = \frac { M g l } { 2 }$