A steel wire is of length 1m, area of cross-section 2 $mm^{2}\ \left( Y = 2\ imes 10^{11}Nm^{- 2} ight).$ How much energy is required for increasing its length by 2 mm.

Question

A steel wire is of length 1m, area of cross-section 2 $mm^{2}\ \left( Y = 2\ 	imes 10^{11}Nm^{- 2} ight).$ How much energy is required for increasing its length by 2 mm.

Dr. Abubacker · Accepted Answer

(b) $U = \frac{1}{2} 	imes Y\  	imes (strain)^{2} 	imes volume\ $
= $\frac{1}{2} 	imes 2 	imes 10^{11} 	imes \left( 2 	imes 10^{- 3} ight)^{2} 	imes 2 	imes 10^{- 6} 	imes 1 = 0.8\ J$

Q. A steel wire is of length 1m, area of cross-section 2 $mm^{2}\ \left( Y = 2\ \times 10^{11}Nm^{- 2} \right).$ How much energy is required for increasing its length by 2 mm.

Explanation

Reviewed by Dr. Abubacker

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