Question

A wire of length $1m$ and radius $4mm$ is clamped at upper end. The lower end is twisted by an angle of 30${}^0$. The angle of shear is

• A. ${0.12}^0$
• B. ${1.2}^0$
• C. ${12}^0$
• D. ${0.012}^0$

Answer 1

The correct option is A ${0.12}^0$

$r=4mm=0.004m$
$L=1m$
$\theta ={30}^0$
$\frac{r}{L}=\frac{{ϵ}_0}{\theta }$ (using standard result)
$\frac{0.004\times {30}^0}{1}={ϵ}_0$
${ϵ}_0={0.12}^0$