If in the above question the Young's modulus of the material is Y, the value of extension x is:

Options

A. `((Wl)/(YA))^((1)/(3))`
B. `((YA)/(Wl))^((1)/(3))`
C. `(1)/(l)[(WA)/(Y)]^((1)/(3))`
D. `l[(W)/(YA)]^((1)/(3))`

Answer

D

Explanation

We know `Y=(stress)/(strai n)=(Wl)/(2Ax)xx(2l^2)/(x^2)`
`Y=(Wl^3)/(Ax^3)` or `x((W)/(AY))^((1)/(3))xxl`
Correct choice is (d).