The arm ABCD of the industrial robot lies in a vertical plane that is inclined at 40? to the yz-plane. The arm CD makes an angle of 30? with the vertical. A socket wrench attached at point D applies a 52-lb · ft couple about the arm CD, directed as shown.
(a) Find the couple-vector that represents the given couple.
(b) Determine the moment of the couple about the z-axis.
