Colin's puzzle for this time: You have ten identical balls at one end of a smooth horizontal2 track, and ten identical balls at the other. You set the two groups rolling towards each other (with plenty of space between them). All of the collisions are perfectly elastic. How many collisions are there?
What Colin doesn't understand: how to calculate $\pi$
A long and rambling ending...
Colin is a Weymouth maths tutor, author of several Maths For Dummies books and A-level maths guides. He started Flying Colours Maths in 2008.
He lives with an espresso pot and nothing to prove.
Colin referred to a quote that was neither Bohr or anyone like that, but Asimov: "The most exciting phrase to hear in science, the one that heralds new discoveries, is not "Eureka!" (I found it!) but "that's funny..."" [↩]