Question

1. The energy stored per unit volume in copper wire, which produces
longitudinal strain of 0.1%, is.........(Y=1.11 1011N/m?)
a) 11 x 103J/m3
b) 5.5x 10+J/m
c) 5.5 x103J/m3
d) 11 x10+J/m​

Answer 1

Answer:

Explanation:

Energy stored per unit volume is given by

E = 1/2 × strain × stress -------(1)

Here E is energy per unit volume .

∵ Young's modulus , Y = stress/strain

so, strain = stress/Y , put it in above equation (1)

E = 1/2 × stress/Y × stress

= stress²/2Y

Given, Stress = x and Young's modulus, Y = y

Then, E = x²/2y

Hence, option (D) is correct