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# Magnet

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Leave one rod on the floor and holding the other rod tight in hand, very slowly move the rod towards the one on floor.

If the rod in your hand is Magnet, the rod on the floor will shake as soon as it comes in the magnetic field of the Rod in the hand.

And if the rod in hand is not Magnet, while moving slowly toward the rod on the floor, as soon as you try to enter the magnetic field you can feel that change when you are entering the magnetic field.

I am 100% sure this will work, wanna try it out?

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Leave one rod on the floor and holding the other rod tight in hand, very slowly move the rod towards the one on floor.

If the rod in your hand is Magnet, the rod on the floor will shake as soon as it comes in the magnetic field of the Rod in the hand.

And if the rod in hand is not Magnet, while moving slowly toward the rod on the floor, as soon as you try to enter the magnetic field you can feel that change when you are entering the magnetic field.

I am 100% sure this will work, wanna try it out?

Hang on, Hang on. the magnetic field would work either way round, a little thing called the General theory of relativity

no somebody is no doubt going to ask can i do any better, we porbably not howeveer i did think of this when i read it:

<!-- s:idea: --><!-- s:idea: --> 1) graphite is not a metal & it conduct electricity

<!-- s:idea: --><!-- s:idea: --> 2) the magnetic and electrical forces are the same thing

<!-- s:idea: --><!-- s:idea: --> 3) you can get LED's that contain no metal parts, failing that a very very thin line of graphite would do.

from this i got this idea: you plan it like this:

KEY : line of graphite, rod

|-----------|

|...........|

LED........#

|...........#

|...........|

|-----------|

(note: the lines are meant to be joined up)

you move the rod from left to right, if the LED flickers then it is your magnet

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wow, this is the first time i have ever seen the admin make a mistake.

a magnet has to have the strongest poles on its ends, this isn't complex at all and if one were to break a magnet they would then have two smaller magnets, nobody can have a mono-pole magnet. it is impossible and has/is still trying to be created.

The impact method would take a long time to see any major change. the hanging method would only work if the two rods were so far away that they had no magnetic field acting on eahother good thing the force drops like 1/(r^2) and r is the distance between the two. the best and smartest way is to use the tip to center method, all others have physical flaws while this one doesn't.

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wow, this is the first time i have ever seen the admin make a mistake.

a magnet has to have the strongest poles on its ends, this isn't complex at all and if one were to break a magnet they would then have two smaller magnets, nobody can have a mono-pole magnet. it is impossible and has/is still trying to be created.

The impact method would take a long time to see any major change. the hanging method would only work if the two rods were so far away that they had no magnetic field acting on eahother good thing the force drops like 1/(r^2) and r is the distance between the two. the best and smartest way is to use the tip to center method, all others have physical flaws while this one doesn't.

Your idea is one of the provided solutions by the host.

"The real magnet will have a magnetic field at its poles, but not at its center. So as previously mentioned, if you take the iron bar and touch its tip to the magnet's center, the iron bar will not be attracted. This is assuming that the magnet's poles are at its ends. If the poles run through the length of the magnet, then it would be much harder to use this method.

In that case, rotate one rod around its axis while holding an end of the other to its middle. If the rotating rod is the magnet, the force will fluctuate as the rod rotates. If the rotating rod is not magnetic, the force is constant (provided you can keep their positions steady)."

Am I missing something here?

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you are missing something. the fact that the magnetic field doesnt run the length of the magnet.

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It's even easier than all that filing and breaking and stuff... Pick up one and try to pick up the other. The one that will pick up the other is the magnet.

stick one rod to the other

What??!!?!?

So the two rods attract, yes, we know one is a magnet. The magnetic attraction between the rods is a function only of the distance between them and the power of the magnetic field. Holding the magnet will not increase it's energy flow and reveal it. If the magnet is strong enough to lift the rod off the table, it will also be strong enough to lift itself off the table when passing the rod over it!

I looked at the top post and thought the exact same thing. But after thinking I realized that if you try to pick up the one laying on the ground by the center then only the magnet with be able to if it's poles are at the ends. To make sure they are then you could simply hold one of the bars by it's very end with just two fingers very gently and move it along the other one without letting them touch. If the bar pulls toward the end then that's where the poles are. If it doesn't pull anywhere, switch bars. This could also be used as another solution in itself. Because, if you are holding the magnet then it will pull just as strongly no matter where it is in relation to the bar leying on the ground. If you are holding the non-magnet then it will pull more strongly when you are over the poles. Please correct me if I am wrong. But I am pretty sure this would work.

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Also, to notalot, those answers weren't by the admin, those were the provided solutions when this puzzle was published. I could be wrong but I don't think he created this puzzle or those answers. (Note, that isn't sarcastic.)

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That's not what the host was trying to say.

Suppose that this is your magnetized rod:

II

II

II

II

The poles can be towards the top and bottom and also the poles can be left to right.

So, imagine that all the "I"s on the left are negatively charged and all the "I"s on the right are positively charged. That would be a magnet whose poles run through its entire length.

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• 4 weeks later...
Magnet - Back to the Logic Puzzles

This is a logic puzzle published in Martin Gardner's column in the Scientific American.

You are in a room where there are no metal objects except for two iron rods. Only one of them is a magnet.

How can you identify this magnet?

Magnet - solution

You can hang the iron rods on a string and watch which one turns to the north (or hang just one rod).

Gardner gives one more solution: take one rod and touch with its end the middle of the second rod. If they get closer, then you have a magnet in your hand.

The real magnet will have a magnetic field at its poles, but not at its center. So as previously mentioned, if you take the iron bar and touch its tip to the magnet's center, the iron bar will not be attracted. This is assuming that the magnet's poles are at its ends. If the poles run through the length of the magnet, then it would be much harder to use this method.

In that case, rotate one rod around its axis while holding an end of the other to its middle. If the rotating rod is the magnet, the force will fluctuate as the rod rotates. If the rotating rod is not magnetic, the force is constant (provided you can keep their positions steady).

Oh, i was watching an episode of Brainiac, and if you had some cereal, you could pour some milk into a bowl, (or any liquid) and then put one bit of cereal floating on the milk, then get the 2 rods, and hover them over the bit of cereal, whichever the bit of cereal responds to the rod that is the magnet, I probably phrased that badly, but you know what I mean. and it's because cereal has iron in it

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For iron to act as a magnet, it has to be electrified. So if you touch one and get zapped, that's the magnet.

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• 2 weeks later...

If cereal has IRON in it, then it has METAL in it. So, you can't use it.

Then, humans have iron in them too (hemoglobin), so we can't be in the room either... so, NOW how do we figure this one out?!!?

Unless certain forms of metals don't count, like oxides (rust in this case) or complex molecules which happen to contain the atomic forms of transition metals (look up a periodic table)...

Since alot of puzzles on this site become debunked due to technicalities, then I hearby declare this one unsolvable, since humans contain iron. And the last time I checked, iron was a metal.

Done.

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Rub your hands really fast over your hair to build up a charge. Hold the ends of each rod up to your hair. One of the ends should repel the hair. That's the magnet.

(This assumes humans are allowed and the human is not)

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• 3 weeks later...

place one rod on the ground (horizontal) and hold the other a short distance away from it in a vertical position like this I _

if the rod on the ground spins (to line up with the rod you are holding) as you move the vertical rod then the rod on the ground is the magnet. If it does not spin then the rod you are holding is the magnet.

Try it with two nails and see.

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wouldnt both of them be magnetic since they are made out of iron lol wouldnt it

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• 2 weeks later...

Put one rod flat on the floor and spin it on its axis two or tree times. If it always stops pointing to the same direction, its a magnet (always points to the north pole). So the other is an iron. But if it points to random directions, its not a magnet, so the oter rod is.

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since there are no metal objects, you could always use the old trick of placing the rods on a piece of cork or wood and float it in water, and then whichever one points a certain direction sonsistently is the magnet.

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1. split both rods

2. reconnect each rod

3. reconnecting the iron rod will not have any effects

4. reconnecting the magnetic rod will have effects, for like poles repel and opposite poles attract

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You did not say that the room had windows and if it did not then how could you tell which way is north. You could not use a compass beacause compasses contain metal in them and you could not bring them into the room.

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Take one rod, beat the heck out of the guy who thought this one up, and see if it sticks to the metal trash can outside, when you throw it away as evidence!

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how can you hang the rods when you dont have anything else in the room but the rods?

i say just snap one of the rods in half and see if they sick together or not, then you can find out which one is a magnet. but you have to be Superman to do that.... hey you never said how strong the rods were

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• 3 weeks later...

This is geting to easy, just old one of the rods a few centimeters above the other one. If the one on the floor come up to meet the other, then the one in your and is the magnet. If the one in your hand is trying to go down to meet the other, than the one in the floor is the magnet.

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I believe this is correct, please feel free to bash me if I'm being an idiot.

if you hold one rod in each hand with your thumbs say as a reference point for wich direction you're holding them. turn them thumbs together or apart and the rods will attract each other.

at this point you can reverse one of the rods. if they continue to attract you just reversed the non-magnet. if they cease attracting you just reversed the magnet.

viola!

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place it against your pacemaker. if you lived, you used the iron. if you see a tunnel, you've got the magnet.

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This is a pretty easy one. All you need to do is to arrange the bars in a T shape. The magnetic strength of magnets is zero at the centre and highest at the poles. So using this arrangement, you can tell which one is the magnet depending on whether the bars attracted each other or not. I havent checked pages 2-4 so if this solution has been given already, please excuse.

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the answer is symple: you need to break the bars and throw them at the walls. then you make a hole and escape. thats how you get out of the room

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