Comments on: Gay magnets?

By: markm

markm — Sun, 31 Jul 2005 14:19:55 +0000

Does the C piece (triangle) attract iron as strongly as the other magnets? If it’s weaker, it not be a good permanent magnet in itself, but rather a material (such as iron) that gets re-magnetized whenever a strong magnet is brought nearby.

When you stick A and B together, can you rotate them (one sliding on the exposed face of the other), or do they have a preferred orientation? In the latter case, they are actually U or bar magnets with both poles present on the exposed face, and either one can stick to magnet C by sliding or rotating them until an unlike pair of poles is lined up.

Finally, A and B might have just one pole on their exposed faces, but C has two.

By: tgirsch

tgirsch — Fri, 29 Jul 2005 18:51:11 +0000

Well that last part I knew.

By: mike hollihan

mike hollihan — Fri, 29 Jul 2005 05:48:22 +0000

Without seeing the pieces, I can’t say what’s going on, but the broken magnets thing is easier. Think of the piece of magnet as a conduit. The field effect flows from one end to the other. Putting two similar ends together is sorta like trying to put two gushing hoses nozzle to nozzle. If you could break the magnet long ways (along the axis of the field effect), you’d see the magnets don’t change!

That’s really imperfect and badly done, but it sorta gives you the idea.

When you break a magnet, you don’t have two pieces of one magnet, but two new, smaller magnets.

By: ben

ben — Fri, 29 Jul 2005 04:19:20 +0000

Magnetism is a weird thing. If I recall correctly, magnetism is a relativistic effect of electric current. I think magnetic objects have a system of eddy currents all over the place. Breaking that fridge magnet probably then changed the nature of the eddy currents ‘n stuff. Either that, or the magnet always was internally repulsive (if that’s possible) and was held together mechanically by it’s material properties ‘n stuff.

who really knows?

By: Jay G

Jay G — Fri, 29 Jul 2005 02:43:16 +0000

Unc,

I think Les’ Katie is too young for a Magna Doodle.

But yes, Les, get one post haste. We have approximately 85 different versions, from the grand assault Magna Doodle complete with detachable magnet-zines all the way to the snub nose concealed versions (with pocket clip).

Keeps the kiddies quiet in the car for minutes at a time…

By: tgirsch

tgirsch — Thu, 28 Jul 2005 20:44:28 +0000

I asked Kevin (a physics nerd if ever one existed), and he said that oddly enough, he was just noticing it the other day and didn’t have an explanation, even though he’s sure there IS one.

By: SayUncle

SayUncle — Thu, 28 Jul 2005 19:08:14 +0000

The magnet is external and covers the entire bottom. In other news, you don’t have a magna doodle? Get one immediately, Junior loves hers.

By: Les Jones

Les Jones — Thu, 28 Jul 2005 18:52:57 +0000

I guess it depends on the shape of the magnets inside the shapes. Like, is the magnet inside the triangle actually a single triangular magnet, or is it three rod-shaped magnets?

By: tgirsch

tgirsch — Thu, 28 Jul 2005 18:51:17 +0000

I can’t get past the thought that it’s a fundamental misunderstanding of how magnetic poles work. I once broke a refigerator magent, and the pieces repelled one another no matter how I tried to put them back together, even though it started off as one big magnet and it was obvious how the pieces were supposed to go.

By: AlphaPatriot

AlphaPatriot — Thu, 28 Jul 2005 17:29:36 +0000

Clearly you have discovered a third pole of magnetism, neither positive nor negative but something else with some of the properties of each so they stick to both the other poles. Give it a name (I suggest bi-ative as it goes both ways), then sit back and wait for your Nobel prize.

By: SayUncle

SayUncle — Thu, 28 Jul 2005 15:54:05 +0000

Tom, I should have been more clear and noted that the portions of magnets exposed would have been +/-. The other portion of the magnet is covered in plastic.

By: tgirsch

tgirsch — Thu, 28 Jul 2005 15:50:36 +0000

“I conclude that one must be positive and one must be negative.”

You conclude incorrectly. One side of each is positive and one side of each is negate. Actually, it’s more accurate to say one end of each is positive and one negative, because it’s not “sides” like a coin; using a quarter as an example, it’s more like George Washington’s head is positive, and his neck is negative.

Also, not only to two positive poles not stick, they repel one another.

By: SayUncle

SayUncle — Thu, 28 Jul 2005 15:29:15 +0000

Not presently. I take magnets (A and B) which only have one side exposed. I put them together and they stick. I conclude they must be positive and negative. Then, I apply A to a third magnet with only side exposed, called C. And they stick. Then I apply B to C and they stick.

By: ben

ben — Thu, 28 Jul 2005 15:24:04 +0000

I can’t quite picture the situation. Can you post a photo?