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coin paradox





Consider two round coins of equal size. Imagine holding one still and then rolling the other coin around it, making sure that it doesn't slip and that the rims are touching at all times. How many times will the moving coin have rotated after it has completed one revolution of the stationary coin? Most people believe that the answer will be once and are therefore surprised to discover that the truth is in fact twice.


Related category

   • PARADOXES