A hollow circular shaft has an outer diameter of $100 \mathrm{~mm}$ and inner diameter of $50 \mathrm{~mm}$. If the allowable shear stress is 125 MPa. the maximum torque (in $\mathrm{kN}-\mathrm{m}$ ) that the shaft can resist is
A hollow circular shaft has an outer diameter of $100 \mathrm{~mm}$ and inner diameter of $50 \mathrm{~mm}$. If the allowable shear stress is 125 MPa. the maximum torque (in $\mathrm{kN}-\mathrm{m}$ ) that the shaft can resist is