A load of `4 kg` is suspended from a ceiling through a steel wire of length `20 m` and radius `2 mm`. It is found that the length of the wire increases by `0.031 mm`, as equilibrium is achieved. If `g = 3.1xxpi` ` ms^(-2)`, the value of young's modulus of the material of the wire (in `Nm^(-2))` is

Options

A. `2.0xx10^(12)`
B. `4.0xx 10^(11)`
C. `2.0xx10^(11)`
D. `0.02xx10^(9)`

Answer

A

Explanation

`Y = (mgl)/(Ae)`