outside diameter of the shaft

Question

A hallow shaft of 1m length is designed to transmit a power of 30 kW at 700 rpm. The maximum permissible angle of twist in the shaft is 1⁰. The inner diameter of the shaft is 0.7 times the outer diameter. The modulus of rigidity is 80 GPa. The outside diameter (in mm) of the shaft is _______

Answer 1

$\therefore$ The outer dia of the shaft is 44.5 mm