Which reminds me of an attractive puzzle I once saw in Wireless World. Suppose you have a lot of pieces that fit together to form a hollow sphere. Think for example of the patches that make up a soccer ball, only thicker perhaps. Suppose further they are all magnetised (magnetized?) with N on what is going to be the outside, S on what is going to be the inside. The fun part is that nothing fundamental is keeping you from adding pieces, side by side, to make a growing sphere. Of course they will repel each other, but that's another problem. All the while, you will have magnetic lines of force from the N on the convex side, through what will eventually be an ever decreasing hole, to S on the concave side. The interesting question is: what happens when you plug up the last hole? And why? What will the force on the last piece be, trying to keep you from plugging the hole shut; compared with the other pieces; larger or smaller?
Can we affix a magnetic style triangle to it in order to manufacture a sundial? OK, this one is a bit obvious, but it keeps the message on topic ;-) Rudolf ----- Original Message ----- From: Tony Moss <[EMAIL PROTECTED]> Cc: sundial mailing list <[email protected]> Sent: Friday, March 30, 2001 9:03 PM Subject: Re: Time Zones > Fernando contributed: > > > Or else we can make the sphere to be > >magnetic and attract our feet, magnetic too, with opposed > >pole ;-) > > Now that IS a novel concept: a magnetised sphere with one pole at its > centre and the other spread all over its surface. A sort of magnetic > Klein Bottle. It's an attractive idea. > > Ouch! > > The dux flensity near the middle would be interesting too. > > Tony Moss > >
