If the physics seems a bit arcane, consider that you probably spent much of the past two weeks seeing the angular-momentum principle in action — at least if you watched the Olympics.

I'll give it a little bit more spin angular momentum, so now I move my left hand towards me and my...

So, let me get a little bit more specific about what we mean by nodal plane and where the idea of nodal plane comes from, and nodal planes arise from any place you have angular nodes.