On Spinning and Toppling Coins -- Did Martin Gardner Change His Mind?

Source

G4G15

Title

On Spinning and Toppling Coins -- Did Martin Gardner Change His Mind?

Contributor

Jim Weinrich

Subject

Magic,Rec Math,MG Legacy,Science

Description

When you spin a penny on a smooth tabletop and let it fall heads or tails, is there a bias toward one side? Or is it a 50/50 expectation? Martin Gardner claimed over the years that there is a heads bias, or a tails bias, but didn't explain why he changed his mind. He consistently maintained that there was probably a slight bevel to the edges of pennies minted in the U.S. I've tested hundreds of pennies for such a bias and have surprising results to share.

Identifier

G15-055-1

Collection

Citation

“On Spinning and Toppling Coins -- Did Martin Gardner Change His Mind?,” G4G Gift Exchange Archive, accessed June 16, 2025, https://g4gexchangearchive.omeka.net/items/show/1703.

Comments

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