fun tricks with rare earth magnets 1

[electricpete]

I bought a set of 10 rare earth magnets from ebay. Each 1/2" x 1" x 1"

As others suggested, I was very careful. Based on what someone suggested on one of the old threads, I taped most of them individually with masking tape to make them easier to handle. (that was a great suggestion... whoever made it... can't remember).

I searched the internet and I found some good fairly easy tricks to impress the kids:

1 - use a magnet to attact a dollar bill... it works. The ink is magnetic.

2 - slide a magnet down between two aluminum bars... it slides very slow due to the eddy currents.

3 - put one magnet on the table. Then underneath the table put another magnet. Don't lead the magnet around.... that is boring and everyone knows what you're doing. Instead, keep on flipping the polarity of the magnet below. The magnet above the table will then keep flipping over like a mexican jumping bean. It's an eerie effect and not what the audience would expect from a magnet.

Any other good tricks or experiments to do wtih magnets?

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[MagMike]

People have usually been amazed when I place a magnet on each side of their hand.

If you can constrain the magnets properly, it also usually amazes people when they try to pressing them together in repulsion.

 

[daveh55et]

Search youtube for rare earth magnet video. Interesting motors and demonstations, also see

http://www.coolmagnetman.com/magindex.htm

 

[nsv]

I live in a small European country where a bicycle is a means of transport rather than a toy. I'm constructing a dynamo to build into the bike's front wheel to supply a small white LED headlamp. I use ø19x5mm Nd-magnets from scrapped tweeter loudspeakers.

NSV

 

[electricpete]

Interesting ideas. I'm gonna build me a dynamo one of these days.

One thing which surprised me a little:
put a steel washer in the palm of your hand. Put a strong neo under your hand on the other side. The steel washer stands straight up and down. That's initially a little surprising since part of the washer has to go farther away from the magnet to get into this orientation. But apparently the force to align with the magnetic field is stronger than the force to pull closer to the magnet in this geometry.

Maybe I'll make some U-tube video's. I did check out the U-tube and there is a ton of interesting stuff there.

This one made me cringe - hammering on a neo with no safety glasses...

http://www.youtube.com/watch?v=MUfIpUQA0wY&NR

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[electricpete]

Here's one called homopolar motor which is about the simplest motor demo I've ever seen. uses a AA battery, a neo magnet and a bent wire.

http://www.youtube.com/watch?v=e_odWP-pHME

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