Put a magnet next to a piece of aluminium or copper and what do you get? Nothing! They’re not magnetic, right? Yup, that’s true. But this isn’t the whole story. Whoosh the magnet past the aluminium without touching it and you may see it twitch. More dramatically, try dropping a powerful magnet down a length of plastic pipe, and then down a similar length of copper plumbing pipe. The plastic pipe has no effect – the magnet accelerates down with gravity. But the magnet lingers and rattles down the metal pipe incredibly slowly. That’s because of eddy currents.
Image credit: Neil Downie
The traditional Christmas Carousel or Christmas Pyramid Carousel is driven round and round by a fan and a bunch of candles. This version of the Christmas Carousel replaces the candle hot air currents with electric...