Question

Two solid circular shafts of radii $R_1$ and $R_2$ are subjected to same torque. The maximum shear stresses developed in the two shafts are ${\tau }_1$ and ${\tau }_2$. If
$\frac{R_1}{R_2}=2then\frac{{\tau }_2}{{\tau }_1}is$

• A. 8

Answer 1

The correct option is A 8
${\tau }_{max}=\frac{2T}{\pi R^3}\frac{{\tau }_2}{{\tau }_1}={\left(\frac{R_1}{R_2}\right)}^3=(2{)}^3=8$

$(\because T_1=T_2=T)$