The increase in length of a wire on stretching is 0.025%. If its poisson's ratio is 0.4, then the percentage decrease in diameter is:

Options

A. 0.01
B. 0.02
C. 0.03
D. 0.04

Answer

A

Explanation

Poisson's ratio,
`sigma=(-DeltaD//D)/(Deltal//l)" "...(1)`
`therefore` % diameter in diameter
`=(DeltaD)/(D)xx100%`
`=sigma(Deltal)/(l)xx100%` [using(1)]
`=0.4xx(0.025)/(100)xx100%`
`=0.01%`