When a wire is subjected to a force along its length, its length increases by 0.4% andits radius decreaes by 0.2%. Then, the poisson's ratio of the material of the wire is

Options

A. 0.8
B. 0.5
C. 0.2
D. 0.1

Answer

b

Explanation

Poisson's ratio `sigma` is the ratio of fractional change in diameter to fractional change in length.
Thus, `sigma (Delta r//r)/(Delta I//I)`
where, r is the radius of the wire
`:. Sigma = (0.2)/(0.4) = 0.5`