A $3\mathrm{.}8-kN$ tensile load $(P)$ is applied to a test coupon made from $1\mathrm{.}6-mm$ flat steel plate $)=200$GPa,$v=(0\mathrm{.}30.$

Problem $02\mathrm{.}064.$b $-$ Poisson's ratio and generalized Hooke's Law, uniaxial loading

Determine the resulting change in the width of portion $AB$ of the test coupon.

The resulting change in the width of portion $AB$ is ${10}^{-6}m.$