I often like to do thought experiments while #cycling and sometimes I can’t think all the way through to the end of the answer. Here’s a recent one for #physicists who specialize in #relativity. A #bike's #wheel rotates such that the bit in contact with the #road is instantaneously at rest with respect to the #ground (no skidding), at least in #NewtonianMechanics. On the other hand, the bit diametrically opposite to it is moving at precisely twice the speed of the #bicycle...
