1. The problem statement, all variables and given/known data I am looking at part C. https://scontent-ord1-1.xx.fbcdn.net/hphotos-xal1/v/t34.0-12/12782422_10205657311624690_1648245885_n.jpg?oh=79b686a8b74392888fab0b070b86627d&oe=56F7E1E4 3. The attempt at a solution Here I am looking at part C. My initial thought is that they have the same kinetic energy. For one puck, this is pure translational, and for the other puck, this is rotational + translational, but regardless the energy which is put into the system with no nonconservative forces acting will be transferred directly into kinetic energy (whether translational or rotational). It is worth noting that I am actually the teaching assistant for this course, and I'm quite ashamed that I am getting the answer wrong; apparently puck 1 has more kinetic energy than two because it has rotational energy whereas puck 2 does not. I do not understand this argument... I do not understand why, when the same amount of energy is being applied to both systems, the pucks have two different kinetic energies. Maybe it has just been too long since mechanics :P Also, all systems are assumed to be ideal here (no energy is being "lost" due to rotation). I do deserve being made fun of for this... let it out.