Auto Mechanics to Quantum Mechanics: Any Questions?

Been a while since we've done this, so let's go.

I have a schtick I do at the beginning of every class where I let my students ask me absolutely any question they have, any question at all, as I say, from auto mechanics to quantum mechanics. When I started up this blog years ago, some former students asked me to revive it on-line, so every once in a while I open it up.

So, if there's a question you've always wanted to ask or something that's just been stumping you, here's your chance. Ask away and I'll try to open up to discussion as many as possible in this week's posts.