A punch for making holes in steel plates is shown in Fig. a. below. Assume that a punch having diameter d = 20 mm is used to punch a hole in an 8 mm plate, as shown in the cross-sectional view (Fig. b). If a force P = 110 kN is required to create the hole, what is the average shear stress in the plate and the average compressive stress in the punch?

Adouble-strand no. 60 roller chain is used to transmit power between a 13-tooth driving sprocket rotating at 300 rev/min and a 52-tooth driven sprocket. a) what is the allowable horsepower of this drive? b) estimate the center-to-center distance if the chain length is 82 pitches. c) estimate the torque and bending force on the driving shaft by the chain if the actual horsepower transmitted is 30 percent less than the corrected (allowable) power.