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Tokyo researchers created the strongest controllable magnetic field in history

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Re: Tokyo researchers created the strongest controllable magnetic field in history

#11
post #8

Earlier quoted context omitted.

> just blew the doors off an iron enclosure intended to contain the massive magnetic field Now, I'm by no means a physicists, but aren't iron enclosures particularly bad at containing magnetic fields?

the iron enclosure was meant to contain the explosion not the field.

Good point - edited!

Re: Tokyo researchers created the strongest controllable magnetic field in history

#13

Earlier quoted context omitted.

> just blew the doors off an iron enclosure intended to contain the massive magnetic field Now, I'm by no means a physicists, but aren't iron enclosures particularly bad at containing magnetic fields?

The magnetic field will tend to concentrate in the iron, meaning it shouldn't propagate as far. Same as using Mu metal for magnetic shielding - https://en.wikipedia.org/wiki/Mu-metal

It shouldn't propagate, but the whole thing should be magnetized at that point, right? While you've got that electro magnet on you could probably stick fridge to the big iron magnet you've created with the container?

Re: Tokyo researchers created the strongest controllable magnetic field in history

#14
post #6
post #3

I'm kind of amazed they were even able to record a video in a 1200 Tesla magnetic field.

Magnetic fields tend to decay with distance from the source which helps.

And broadly speaking by the cube of the distance from the source apparently. But in this case it decays from a mind-boggling starting level by everyday life standards. If that camera is 5 meters away from the source the field there is still about 10 Tesla. I think that's about an order of magnitude more than most MRI machines for clinical purposes, and those already warrant a good deal of care with effects on metals.

Re: Tokyo researchers created the strongest controllable magnetic field in history

#15

Earlier quoted context omitted.

The magnetic field will tend to concentrate in the iron, meaning it shouldn't propagate as far. Same as using Mu metal for magnetic shielding - https://en.wikipedia.org/wiki/Mu-metal

It shouldn't propagate, but the whole thing should be magnetized at that point, right? While you've got that electro magnet on you could probably stick fridge to the big iron magnet you've created with the container?

Depends on how the field moves relative to the iron. If it expands then contracts, which seems highly likely, the overall effect on magnetizing the iron could be surprisingly low, as far as I am aware. Though I could be wrong on this.

edit - ahh, reading through you mean during the experiment, rather than it being left magnetized afterward.

During the test it should focus field lines within it. The overall strength of the field will remain the same, but field lines will be concentrated on the cage, meaning it does not propagate as far.

Though there should be people on here that will be able to explain this better than I can. And correct me if I am talking rubbish. I am solidly an amateur on this, and there are definitely some professionals floating about.

Re: Tokyo researchers created the strongest controllable magnetic field in history

#16

Earlier quoted context omitted.

> just blew the doors off an iron enclosure intended to contain the massive magnetic field Now, I'm by no means a physicists, but aren't iron enclosures particularly bad at containing magnetic fields?

From a tiny bit of experience, I know that industrial electromagnets (think of the ones they use to pick up steel at a scrap yard) often have an iron/steel housing that is used as a "return path" for the field. The front face of the magnet has a field that projects out into the air, but the field on the back face gets channeled into the housing.

Alnico horseshoe magnets are often sold with a keeper bar: https://en.wikipedia.org/wiki/Magnet_keeper

Re: Tokyo researchers created the strongest controllable magnetic field in history

#17

It blows my mind that we can compress a magnetic field with chemical explosives. I wouldn't have expected them to interact much at all.

>> I wouldn't have expected them to interact much at all.

They don't interact directly:

https://en.wikipedia.org/wiki/Explosively_pumped_flux_compre...

Re: Tokyo researchers created the strongest controllable magnetic field in history

#18

Vice really needs to hire some proofreaders.

I hate when I see a sciency article from them. They are great with human interest stuff (if you like their spin) but the technical stuff is always lacking. You can tell where the writer hits their wall of undertanding and tries to fill it with quotes instead of working with someone knowlegable on the subject.

Re: Tokyo researchers created the strongest controllable magnetic field in history

#20
post #2

Anti-clickbait: they didn't blow up their lab, just blew the doors off an iron enclosure intended to contain the massive shockwave, which turned out to be even more massive than intended. Still impressive though!

I was waiting for Gordon Freeman to emerge from behind the machine with his crowbar...
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