Statics and Strength of Materials. Professor Mark Martson. Please don't copyright me again.
5.1 Calculate the force a punch press must exert if it is to punch out a large washer from a strip of 5-mm thick sheet of steel with an ultimate shear strength of 375 MPa. The washer dimensions are as follows: hole diameter of 4 mm, and outside diameter of 9 mm. (Similar to textbook problem 9.38)