1997/02/01 by Tadashi F. Tokieda, Tadashi Tokieda · 1 citation
Physics and Astronomy · #Experimental and Theoretical Physics Studies
paper · doi:10.1080/00029890.1997.11990614
'A weight is attached to a point of a rough weightless hoop, which then rolls in a vertical plane, starting near the position of unstable equilibrium. What happens, and is it intuitive?' The problem just quoted is from Littlewood's delightful Miscellany [1, p.37]. As is often the case in phenomena involving a no-slip constraint ('rough' indicates that the hoop is to roll without slipping), what happens is rather unintuitive. Declares Littlewood: 'The hoop lifts off the ground when the radius vector to the weight becomes horizontal.'