A steel wire of length 2 m is stretched by 2 mm . The cross sectional area of the wire is $4 \mathrm

Question

A steel wire of length 2 m is stretched by 2 mm . The cross sectional area of the wire is $4 \mathrm{~mm}^2$. If the Young's modulus is $2 	imes 10^{11} \mathrm{~N} / \mathrm{m}^2$, the elastic potential energy stored in the wire in stretched condition is

Professor PC Thomas Classes · Answer

Energy $U = \frac{1}{2} 	imes 	ext{stress} 	imes 	ext{strain} 	imes 	ext{volume} = \frac{1}{2} 	imes \frac{YA}{L} 	imes \Delta L^2 = 0.8 \mathrm{~J}$.