Powerful Magnets: Benefits & Risks

[Pengwuino]

http://livescience.com/technology/ap_050729_super_magnet.html

Does anyone know if there's anything bad about this? Some people on this other forum act like its the end of the world but its only about 21 tesla from another article. There saying you could rip out iron from peoples blood or draw in people from miles away lol. Anyone know the real story? :)

 

[Gokul43201]

1. 21 T is not a big deal by itself. The magnet in out lab goes up to 17 T when I'm working about 10 feet away. I must be careful not to be walking by with my credit cards and such stuff on me. Also I don't want to carry steel (or other magnetic) objects nearby. I don't have to be miles away to feel safe.

2. This particular magnet IS a big deal, not for the field strength alone but because of the large volume over which this field is maintained and homogeneous. That takes a lot of energy and some very careful design work.

 

[theCandyman]

The article is trying to make the magnet look impressive by comparing it to the magnetic field of the earth. I find that kind of funny.

 

[Mk]

I laughed at the iron in the blood part.

Here's a 45'er
http://nmr.magnet.fsu.edu/facilities/45T_32mm_TLH.htm

But 21 Tesla IS a lot.

I heard that in NMR facilities the areas are color coded depending on how many Gauss.

 

[Gokul43201]

Oh, when I said 21T is not a big deal, I meant that it wouldn't suck things from miles away ! NMR magnets are usually about 10 to 15T. Our 17T magnet is the biggest in the department and one of the biggest on campus, but it's pretty common around the country (to have magnets of that strength).

 

[Mk]

Definitely, what I ment was that 21 T is quite a bit more than the average person experiences everyday.

 

[hypatia]

could rip out iron from peoples blood

guess there is a advantage to being slightly anemic

 

[Gokul43201]

Definitely, what I ment was that 21 T is quite a bit more than the average person experiences everyday.

About 420,000 times more, eh ?

 

[Mk]

Gokul! You just exposed my deepest darkest secret! Delete your post[/size] IMMEDIATELY

 

[Ivan Seeking]

When I worked on MRI units, back when they were new to medicine and had field strengths of up to 1.5T, I had a favorite joke to play on the docs.

Did you hear about residual affects being reported by NMR (MRI) patients?

No! What...?

It looks like the iron in the blood exhibits enough magnetic hysteresis to cause problems later.

Really! What happens...?

They tend to walk north.

 

[Entropy]

There saying you could rip out iron from peoples

Watching too much X-2 are we?

 

[Ivan Seeking]

Here are a couple of pictures showing what happened when a floor buffer got too close to an MRI magnet.


http://img106.echo.cx/img106/51/whatwasit4pz.jpg

http://img106.echo.cx/img106/3733/mriscrubber7ro.jpg

 

[Kakarot]

LOL that's crazy. btw can a magnet placed over a part of your body like a vein help accumulate iron in that spot and start a clot? or is iron in your blood bonded to something so that it isn't magnetic anymore

 

[loseyourname]

Watching too much X-2 are we?

That's exactly what I thought. I wonder what the power of Magneto's field is.

 

[Gokul43201]

LOL that's crazy. btw can a magnet placed over a part of your body like a vein help accumulate iron in that spot and start a clot? or is iron in your blood bonded to something so that it isn't magnetic anymore

I'd be very, very surprised if hemoglobin were magnetic. What makes metallic iron (ferro)magnetic is (among other things) the spacing between neighboring Fe atoms. In hemoglobin, the Fe atoms (actually Fe^2+ ions) are separated by the intermolecular separation. There is no possibility of a magnetic exchange interaction. Blood just can't be magnetic.

 

[Mk]

But water is diamagnetic, blood is chock full of water.

And what about the frogs and spiders I see in high field strength chambers that are floating around?