What’s the probability of a coin landing on its side?

Psycho Sonny said:
my family owns a restaurant and one table left a £3 tip on the table all pound coins, wen i went to clear the table i dropped one of the coins and it landed on its side and rolled about 5 feet and stopped on its side, a pound coin is a lot fatter than most coins an i reckon the odds of it landin on its side are a lot lower than say a 2p

See but you didn't *flip* the coin, so it had little/no sideways momentum, that's the major problem.
 
Psycho Sonny said:
well if you have to flip it then the chances of it landing on the side is zero simple as

why zero? aslong as the side faces the deck it has a chance and flipping a coin the side does face the deck so it has to be possible.
 
Mohinder said:
See but you didn't *flip* the coin, so it had little/no sideways momentum, that's the major problem.
Also, the fact that it's fatter means it's inherently more stable and it also has a much lower centre of mavity.
 
I consider the question asked in the OP to be fairly dull, but here's something that's maybe more interesting.

While googling for any statistics about coins landing on their sides, I came across a research paper by two guys who purported to show (using mechanical arguments) that a flipped coin has approximately a 51% chance of landing the same way as it was when you flipped it.

Curious to see whether I could confirm this by experiment, I started flipping a 2p coin with my thumb, then catching it with the same hand and slamming it down on the back of my opposite hand. I always started the coin heads up, and I recorded whether it came up heads or tails.

I got bored after 100 flips, so my data set is small, but I recorded 61 occurences of heads and only 39 of tails. Assuming that there's a 50/50 chance of either H or T, then there's approximately a 1.76% chance of getting 61 or more heads out of 100 flips. So was my experiment mere statistical anomaly, or do I really have a technique of flipping coins that makes it significantly more likely to land the same way up as it started? If the latter, I foresee a devious profit-making opportunity... ;)
 
Surely there is a very good chance of it landing on its side. but not staying on its side.

Landing to me indicates that it is the first part to hit the surface after leaving your hand :D
 
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