(2590) The low speed shaft of a wind turbine is 3 m long and has a diameter of 0.58 m. It is made of steel with a shear modulus of G-80 GPa. It is rotating at 11.5 rpm and the turbine is generating 6 MW. a) Find the applied rotor torque (Nm), assuming an overall drive train efficiency of 90%. (b) Find the angle of deflection, deg (c) Find the strain energy stored in the shaft, J (Note: this does NOT refer to kinetic energy due to rotation) (d) Find the maximum stress in the shaft, Pa. JG , L Hint: The rotational stiffness of a shaft,忽is given by k and J- polar area moment of inertia, where L = shaft length