Predicting Coin Spin Patterns

[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

 

[CellCoree]

Hello benjo0101,

Thank you for sharing your experience with coin spinning and seeking input from others on the possible factors that may influence the spinning patterns. I can offer some insights into this phenomenon.

Firstly, the spinning of a coin is influenced by a number of factors such as the weight, shape, and surface texture of the coin, as well as the force and speed of rotation. These factors can affect the distribution of mass and the aerodynamics of the spinning coin, which can result in different patterns.

For example, a heavier coin may require more force to spin and can result in a more stable and consistent circular pattern. On the other hand, a lighter coin may be more sensitive to changes in force and may produce more erratic spinning patterns.

The shape and surface texture of the coin can also play a role in the spinning patterns. For instance, a coin with a rougher surface may create more friction with the air and result in a slower and more stable spin, while a smoother coin may have less friction and spin faster with less stability.

Furthermore, the speed and direction of rotation can also influence the spinning pattern. Centrifugal force, which is the outward force experienced by an object in circular motion, can cause the coin to move away from the center of rotation and create a more circular pattern. Changes in the speed or direction of rotation can affect the balance of centrifugal force and result in different patterns.

In conclusion, the spinning patterns of a coin can be influenced by multiple factors such as weight, shape, surface texture, and speed of rotation. While it may seem like a simple game, it is actually a complex interplay of various physical forces. I hope this helps to shed some light on your observations and discussions. Keep experimenting and having fun!