A hockey puck of mass m and radius r slides across frictionless ice. It has translational speed v to the right and rotational speed w clockwise. It grazes the "top" end of a rod of mass m and length 2R which is initially at rest on the ice. It sticks to the rod, forming a rigid object that looks like a lollipop.

a) In the special case of v=Rw, what is the resulting angular speed of the lollipop?

b) How much energy is lost during the collision? How do you explain the fact that energy is lost, given that the v=Rw condition implies that the contact point on the puck touches the rod with zero relative speed.

c) Given w, show that v should equal 6Rw/5 if you want the minimum amount of energy to be lost.