$!$

Required Information

A solid $1040$ hot$-$rolled steel shaft $38\mathrm{.}00$ in long has a rectangular cross section of $2\mathrm{.}5$ in $3\mathrm{.}6$ in $.$ The shaft transmits a

torque of $28\mathrm{.}00$ klp $-$In at an angular velocity of $490$ rpm $.$

Determine the maximum value of the torsional shear stress.

The maximum value of the torsional shear stress is

kpsl$.($Round the final answer to three decimal places.$)$