Looking for quidance on calculating the mass at an impaction point of a swinging hammer. The hammer is set up to be swung pneumatically just at the edge of the handle in the horizontal plane. I understand the calculation E=1/2mv^2. Velocity is being measure just before the impaction point. So i'm happy with that and know the value. Let say v=5m/s. The question is on mass. the hammer head has a mass M1 and the handle has a mass M2. What is the mass to be used at the impaction point. M2, M2+M1, center of mass (but then how do i figure that), some other method? I want to simply calculate the energy being imparted at that point.