Hear Ye! Since 1998.
Please note: This post is at least 3 years old. Links may be broken, information may be out of date, and the views expressed in the post may no longer be held.
28
Jun 09
Sun

The Train Problem

What keeps train wheels on a track? When a train rounds a bend, the outer wheels have to travel a further distance than the inner wheels, and therefore the outer wheels have to spin at a quicker rate to cover that distance than the inner wheels cover. The problem is that pairs of wheels on a train are connected by a solid metal axle, so the wheels can’t spin at different rates. So, how does it work?

Richard Feynman explains.