Example $4$

Rotation is prevented at $B$ and $D.$ A $50$ Nm torque is applied at $E$ of shaft EAB.

$r_{AB}=7\mathrm{.}5mm,r_1=60mm,G=77$GPa

$r_{CD}=6mm,r_2=40mm,$

Find,

a$)$ maximum shearing stress in $CD$

b$)$ the angle of rotation at $A$

To calculate these we need to find torque on shaft $AB$ and $CD$