Question

What is the force required to be exerted by the punch in order to shear out the blank (form a circular disc) of 20 mm diameter and 1.5 mm thickness and having a shear strength equal to 300 MPa?

         (a) 9.0 kN           (b) 18.0 kN      (c) 28.3 kN      (d) 45.0 kN