This was a great lecture/presentation. I loved it; it was a feast for a mechanical engineer.
After watching Quiz: Did you hear the terms drag co-efficient and dynamic similarity or similitude? The drag on a body (e.g. vehicle or spacecraft) passing through a fluid (such as the atmosphere) experiences a drag force (to slow it down) proportional to the density of the fluid, the velocity squared, a reference area of the body and a drag coefficient or scale factor. Here’s an explanation on Widipedia http://en.wikipedia.org/wiki/Drag_equation. Also, dynamic similarity is the science of testing small models (remember the small round disc he pulled out of his pocket during the presentation) with results applicable to large models. Again, here’s an explanationhttp://en.wikipedia.org/wiki/Similitude_%28model%29 . These guys are doing a great job developing technologies based on an excellent knowledge of the laws of nature.