An elastic material of Young's modulus Y is subjected to a stress S. The elastic energy stored per unit volume of the material is

Options

A. `(YS)/(2)`
B. `(S^(2))/(Y)`
C. `(S^(2))/(2Y)`
D. `(S)/(2Y)`

Answer

C

Explanation

(c) Strain `=("Strain")/(Y)=(S)/(Y)`
Now, energy stored per unit volume `=(1)/(2)xx"stress"xxx"strain"`
`=(1)/(2)xxSxx(S)/(Y)=(S^(2))/(2Y)`