Question

A steel wire of diameter 1 × 10^-3 m is stretched by a force of 20 N. Calculate the strain energy per unit volume.

(Y_steel = 2 × 10¹¹ N/m²)

Answer 1

Given: d = 1 × 10^-3 m, r = 5 × 10^-4 m,

y_steel = 2 × 10¹¹ N/m²

To find: Strain energy per unit volume

Formula: Strain energy per unit volume

= \(\frac{1}{2}\) × \(\frac{(stress)^2}{Y}\)

Calculation:

From formula.

Strain energy per unit volume

= 1621 J

The strain energy per unit volume of the steel wire is 1621 J.