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# Need Help Synchronise Two Spinning Magnets

Discussion in 'The Projects Forum' started by roonyroo, Jul 18, 2012.

1. ### roonyroo Thread Starter New Member

Jul 18, 2012
1
0
Im trying to spin a magnet using another magnet attached to a small fan

The problem is the magnet spins fine, at low speeds, but if I increase the speed, the magnet attached to the fan overshoots the 2nd magnet

One magnet is attached to a small fan, the other magnet is attached to a cardboard circle attached to a stick ...

So how can I keep the 2nd magnet attached to the stick spinning at a higher speed, using the magnet attached to the fan?

Is there a formula I can use to predict the amount of magnetic force required to spin other magnets at high speed?

2. ### wayneh Expert

Sep 9, 2010
16,102
6,220
Boy, is there! Physicists are nothing if not fond of formulas.

But really your problem is just inertia and resistance. You need the second magnet to spin very freely on a bearing and I think it will eventually speed up enough to get "caught" by the driving magnet. The key is that each pass of the driver must give more acceleration to the passenger than is absorbed by spinning resistance.

3. ### Markd77 Senior Member

Sep 7, 2009
2,796
595
Stronger magnets or decrease the distance between them. Also if you can use more than one magnet on each disk (equally spaced) that would be much better because it balances the weights and also off-axis forces from the magnets.