A spinning coin rotates as it wobbles. The rate of rotation is (1/cos(θ) - 1) of the rate of wobble. Draw an arrow on a coin and check it yourself!\r<br>\r<br>The notes from the whiteboard are available here:\r<br>\r<br>\r<br>Here are the videos of the disk spinning:\r<br>NORMAL SPEED: \r<br>10% SPEED: \r<br>\r<br>Music by Howard Carter\r<br>Design by Simon Wright\r<br>\r<br>MATT PARKER: Stand-up Mathematician\r<br>Website: \r<br>Maths book: \r<br>Nerdy maths toys:
