53. Calculate the motor horsepower requirements for machining a 3 inch round 1020 Steel work piece with a depth of cut of 0.020 inches, a feed rate of 0.008 inches/rev, 70% efficiency, 200 ft/min cutting speed, and a Unit Horsepower of 1.5. a) Find MRR a. Use Q = 12 x d x fr x Vc. b) Find Unit Power a. Use U = Ps/Q and solve for Ps MRR= c) Find Power at Motor a. Use: Pm Ps/E = Power at Spindle (PS) = Power at Motor (PM): =