mechanics of materials
posted by dmkp .
A hollow circular shaft has an external diameter of 160mm and an internal diameter of 120mm. Calculagte the polar second moment of areaof the shaft and the maximum and minimum shear stress produced when the applied moment is 40kN m.

D=150 mm =0.15 m d= 120 mm = 0.12 m
T=40 kN•m = 40000 N•m.
J=π(D²d²)/32 =...
T/J=Gθ/L=τ(min)/r,
τ(min) = Tr/J=Td/2J=...
T/J=Gθ/L=τ(max)/R,
τ(max) = TR/J=TD/2J=...