A uniform thin rod of length and mass rests at equilibrium on a frictionless…
PHYSICS · Multi-part · AP · Physics C: Mechanics · Linear Momentum · Linear Momentum
Problem
A uniform thin rod of length L and mass M rests at equilibrium on a frictionless horizontal surface. A small blob of putty of mass m slides across the surface with speed v along a line perpendicular to the rod. The putty strikes the rod at a point that is a distance L/4 from the rod’s center and sticks to it. Ignore all external forces during the very short collision interval.
(a) State the expression for the moment of inertia of the rod about its center.
(b) Determine the speed Vcm of the center of mass of the combined system immediately after the collision.
(c) Determine the magnitude of the angular speed ω of the system about its center of mass immediately after the collision.
(d) Calculate the fraction of the putty’s initial kinetic energy that is lost during the collision and describe where that energy goes.