We'll start with a pendulum, just because it's simple; as we look close, it might not be as simple as it seemed at first. The usual analysis of a pendulum's motion results in a prediction of perpetual periodic motion, but we know that that's not realistic. Everyday experience tells us that the pendulum will end up motionless, pointed down. How are linear and angular momentum conserved through this process? That's what I'm going to talk about today.