Whan a wire is stretched, the increase in its length is 0.02%. What is the percentage decrease in its diameter if its Poisson's ratio is 0.3 ?

Options

A. `0.005`
B. `0.006`
C. `0.002`
D. `0.001`

Answer

B

Explanation

Poisson's ratio `sigma = (Delta D//D)/(Delta l //l) :. (-Delta D)/(D) = sigma(Delta l)/(l)`
and percentage decrease in diameter
`= (-Delta D)/(D) xx 100 = sigma (Delta l)/(l) xx 100`
`= 0.3 xx (0.02)/(100) xx 100`
`= 0.006`