What Factors Influence the Spinning Patterns of a Coin?

[benjo0101]

Hi all,

Im new here so please be gentle.

Whilst in the pub last night a game was started with spinning a coin. We got to the point where we could all spin the coin with our hands in a circle around the salt shaker, about 3cm diameter. We then moved on to the pint glass and achieved that just about with the coin hitting the pint glass almost exactly as it reached a full arc around the glass. We then moved up to the much bigger jug of beer, 13cm in diameter and couldn't do it. No matter what we did with the speed we couldn't get the coin to do it. At this point we started to discuss the types of things that cause the coin to spin in the way it does and spin in the circular patterns.
The weight of the coin? The patterns on the edges/sides? The age/quality of the coin? The speed of rotation? Centrafugal Force? Witchcraft?

Anybody got any ideas what causes it to spin in the way it does?

I must point out quite a large amount of beer had been consumed by the end of this experiment so I cannot say we weren't just being fools but there isn't anything that obvious on the internet about it.

Anything you guys can think of would be great!

Cheers

benjo0101

 

[benjo0101]

Nobody?

 

[Stephen Tashi]

Are there any Youtubes of similar experiments?

 

[wisvuze]

I don't know too much about chaos theory, but I think that chaos theory would tell you that it would be futile to attempt to determine *everything* that causes a coin to spin the way it spins. Of course, there are "ideal" physical situations that can approximate the coin, but the "exact" situation would be too complex
even if you had enough known variables and knowledge of causal effects, putting it all together would perhaps lead to some "radical"/discontinous/unexpected results