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        riddles >> easy >> Magnet detection
        
(Message started by: inquisitive on Dec 12^th, 2007, 12:45am)

Title: Magnet detection
Post by inquisitive on Dec 12^th, 2007, 12:45am

Guys,
The search didnt yield any result, so i am posting the question from the easy riddles.

You have two cylindrical rods of iron, identical in size and shape. One is a permanent magnet. The other is just non-magnetized iron -- attractable by magnets, but not permanently magnetic itself. Without any instrument, how can you determine which is which?

I could not find the solution. I would need atleast a thread to detect. :(

Title: Re: Magnet detection
Post by towr on Dec 12^th, 2007, 12:49am

[hide]The middle of the magnetic rod isn't much more magnetically attractive then the other rod[/hide]

Title: Re: Magnet detection
Post by JiNbOtAk on Dec 12^th, 2007, 3:23am

on 12/12/07 at 00:45:08, inquisitive wrote:

Without any instrument, how can you determine which is which?

Use a third non magnetized iron rod to test both these rods.. ;D

Title: Re: Magnet detection
Post by tiber13 on Dec 12^th, 2007, 3:55am

would a real magnet stick to you if you had enough iron in your blood?

Title: Re: Magnet detection
Post by towr on Dec 12^th, 2007, 4:01am

on 12/12/07 at 03:55:55, tiber13 wrote:

would a real magnet stick to you if you had enough iron in your blood?

Well, by definition, if it wouldn't stick, you wouldn't have enough iron in your blood.
I suppose the question is, can you have enough iron in your blood for a magnet to stick to you (by attracting said iron).
As far as heamoglobin is concerned, I'd say no. I suppose you could have pellets of raw iron injected into the bloodstream, but that would be cheating, as well as, quite probably, lethal.

Title: Re: Magnet detection
Post by JiNbOtAk on Dec 12^th, 2007, 4:04am

According to Magneto..[hide]yes. [/hide]

Title: Re: Magnet detection
Post by tiber13 on Dec 12^th, 2007, 5:12am

well, what if you had as much iron in youre blood as unlethally possible, and a Huge magnet(like my favourite word, dysporium) would it work then?

Title: Re: Magnet detection
Post by towr on Dec 12^th, 2007, 5:35am

on 12/12/07 at 05:12:18, tiber13 wrote:

well, what if you had as much iron in youre blood as unlethally possible, and a Huge magnet(like my favourite word, dysporium) would it work then?

I very much doubt it.
With a large enough magnetic field, due to water's diamagnetism you'll be repulsed instead.

Title: Re: Magnet detection
Post by Grimbal on Dec 12^th, 2007, 7:59am

on 12/12/07 at 03:23:32, JiNbOtAk wrote:

Use a third non magnetized iron rod to test both these rods.. ;D

A fridge works well also.

Another possibility is to attach them to a thin thread and see which one knows where north is.

Title: Re: Magnet detection
Post by tiber13 on Dec 13^th, 2007, 4:15am

ok.. ok..
but would you be able to stick someone to the roof with enough(powerful) magnets?

(assume you stick them to the inside back of your shirt)

And the roof is metal

Title: Re: Magnet detection
Post by towr on Dec 13^th, 2007, 4:52am

on 12/13/07 at 04:15:08, tiber13 wrote:

ok.. ok..
but would you be able to stick someone to the roof with enough(powerful) magnets?

If the roof is the right sort of metal, sure. I'm fairly sure it has been done.

Title: Re: Magnet detection
Post by Grimbal on Dec 13^th, 2007, 4:58am

You just need large enough magnets. And a strong shirt.

Title: Re: Magnet detection
Post by cool_joh on Dec 14^th, 2007, 2:30am

[hide]Place the rods like T - shaped. If they stick together, then the lower rod is magnetic. If they don't, therefore the upper rod is magnetic.

The reason is the middle part of a magnetic rod doesn't attract metal.[/hide]

But I'm still doubt about this.

Title: Re: Magnet detection
Post by cool_joh on Dec 14^th, 2007, 2:32am

on 12/12/07 at 03:23:32, JiNbOtAk wrote:

Use a third non magnetized iron rod to test both these rods.. ;D

The third iron is also considered an instrument, isn't it?

Title: Re: Magnet detection
Post by cool_joh on Dec 14^th, 2007, 2:39am

Is [hide]river[/hide] or [hide]ocean[/hide] considered an instrument? If it's not, you can [hide]place the iron rod on the surface of a calm river or the ocean. If it is magnetic, then the iron will move according to the direction of the North Pole and the South Pole.[/hide]

Title: Re: Magnet detection
Post by tiber13 on Dec 14^th, 2007, 6:01pm

thanks for the reassureance

*Sticks brother to roof*

Title: Re: Magnet detection
Post by JiNbOtAk on Dec 14^th, 2007, 9:19pm

on 12/14/07 at 02:32:11, cool_joh wrote:

The third iron is also considered an instrument, isn't it?

Not to me, I consider it just another piece of material. :P

Title: Re: Magnet detection
Post by jollytall on Jan 4^th, 2008, 4:05am

on 12/14/07 at 02:39:42, cool_joh wrote:

You need Scuba diving equipment too. It will sink AND turn at the same time. I am not sure you will be able to notice the turn piece.
But also because the two materials do not have the same density the sinking speed shall also be different. So you can check that instead of orientation.

Title: Re: Magnet detection
Post by Icarus on Jan 4^th, 2008, 5:48pm

on 12/12/07 at 03:55:55, tiber13 wrote:

would a real magnet stick to you if you had enough iron in your blood?

Ferromagnetism works by the grains in iron aligning themselves with the magnetic field. The iron in your blood is bound in the hemoglobin, so it doesn't form grains. Without the grains, I believe (but do not have a source to back me up), that iron atoms are effectively paramagnetic. That is, they are weakly affected by magnetic fields.

Title: Re: Magnet detection
Post by ephyzy on Mar 24^th, 2010, 12:16am

Looks like cool joh has ironed this one out :D

[hideb]
Place the rods like T - shaped. If they stick together, then the lower rod is magnetic. If they don't, therefore the upper rod is magnetic.

The reason is the middle part of a magnetic rod doesn't attract metal.
[/hideb]

Title: Re: Magnet detection
Post by Strigoides on Mar 26^th, 2010, 8:13pm

[hideb]If you can bend the lengths of iron (possible if they are thin) then you could bend each iron rod so that the ends can touch, and see if each end repels the other, if it does, it's then magnet, if not, it's not the magnet[/hideb]