QUOTE (bleedingelite @ Mar 17 2008, 06:27 PM)

A couple of things that I noticed:
1. the pin wheel thing was moving pretty slowly and erratically. How do you explain it when the maker of the video can say beforehand which direction it will spin?
2. there was clearly condensation on the inside of the bowl.
1. Has this ever happened? Has someone been able to produce a pin wheel under glass video where the direction of the spin is controlled?
Also of note is that in playing with pin wheels myself I have noticed one can gain control over the direction that it spins rather quickly. This is done even more simply is the same pin wheel is used over and over, the balance point is kept the same, care is taken to balance the paper accurately and most other things are kept the same. I found that using the same pin wheel I could gain control over it in one sitting but the next time it would not work the same way.
2. Obviously Llynx just proved a concept. One could easily heat one plat and cool the bowl or vice versa. It doesnt take a lot to get the convection current going. Simple things could easily be done that would be invisible to the viewer (and not necessarily conscious cheating) yet create the convection currents.
Kevin A.