Magnets and Computers

[Narnia]

I've heard that technology and magnets don't mix. I've heard that magnets will destroy computers. However I have a phone that uses software, like a computer does, yet it's carrying case is magnetized. I have a Bluetooth headset and it's case is magnetized. I also have several such devices with magnetic carrying cases. Did they find a way to make computers magnet proof, has the danger of magnetism been exaggerated and is not really as bad as all my teachers have maintained, or is it just that they carefully designed the case for the phone so it would not affect this particular design of phone but is still a danger to other devices? And finally, is it safe for me to use this phone case while I'm using my laptop or should I keep it at least x number of feet from my computer at all times? Thanks.

PS: What exactly will a magnet do to a computer and why is it a hazard?
PS: I wasn't sure whether I should place this in the science category or the computer category. If this is misplaced, please tell me so I can ask an admin to move it. Thanks.

 

[aimeeandbeatles]

A hard drive's essentially a big magnet. So its slightly overstated that a fridge magnet would wreck your hard drive (it could, however, wreck floppy disks. Ive done that by mistake. Oops) Check out this.

And either ways, a magnet big strong enough would rip the earth apart. But you'd be dead if that happened.

 

[Earthling]

aimee actually provided a rather good link so I shouldn't have bothered to lurk around and answer this. But it's the same idea.

Firstly, modern memory storage technology is far less vulnerable to being erased by exposure to strong magnetic fields. Hard drives used magnetic storage but flash or eeproms you might find in portable devices (I don't know as much about cell phones as I could) isn't at much at risk at all.

Magnets can still mess with active, running technology like lcd screens very easily but again, not necessarily permanent damage.

Another interesting thing along the same lines - you know that you could likely take apart various circuit boards you'd find from a computer, wash them in water, and have them work fine as long as they are thoroughly dried out. Water does no harm to hardware at all as long as nothing is running/powered on. But again, the concern with magnets was almost always just about erasing memory, and fewer things are affected these days.

 

[Narnia]

So the worse it could do is make my screen look funny if the magnet is right beside it but can't do any permanent damage, right?

 

[aimeeandbeatles]

Couldnt you screw up a CRT by messing with a rare earth magnet? I think you could fix it by degassing it.

 

[Earthling]

I don't claim to be an expert at all on screens so I wouldn't take my advice as a license to go mess around or whatever, but most likely your average magnet a person could easily get, like a fridge magnet, on current technology, no, would not cause permanent damage of any sort, you'd just get weird colors on your screen and so on.

 

[Speedo]

A hard drive's essentially a big magnet. So its slightly overstated that a fridge magnet would wreck your hard drive

Magnetic fields are perfectly capable of damaging hard drives, because mechanical drives store data by magnetizing sections of metal plates to represent binary data. Hit the drive (specifically, its platters) with a strong enough field, and the data stored within is damaged [corrupted] or completely wiped out.

I wouldn't risk rubbing even a fridge magnet directly on a hard drive (odds are it wouldn't do a thing... but it only needs to corrupt a few bits to cause you major headaches), but if the drive is inside a computer, even a laptop, you'd have to be playing with some extremely strong rare earth or electromagnets to have any real danger of damage - the separation provided by the computer case is enough to significantly reduce the strength of the magnetic field.

 

[tokala]

Couldnt you screw up a CRT by messing with a rare earth magnet? I think you could fix it by degassing it.

DO NOT screw around with supermagnets around a CRT. Been there, done that, and overdone it

While the in-build degaussing function is able to fix some minor misadjustment, and a screwdriver demagnetizer can fix even more serious ones, I managed to permanently damage the mask of the monitor I was fooling around with

 

[aimeeandbeatles]

today I asked the hardware teacher about it. He said you shouldnt wave a fridge magnet over a hard drive. Haha. What I meant is a fridge magnet wrecking your hard drive by sitting on the desk.

I have one of those magnetic building sets which is how I screwed up the floppy disk. Luckily nothing important on it, just some of my moms schoolwork I was 7 or 8 though....

 

[Narnia]

DO NOT screw around with supermagnets around a CRT. Been there, done that, and overdone it

While the in-build degaussing function is able to fix some minor misadjustment, and a screwdriver demagnetizer can fix even more serious ones, I managed to permanently damage the mask of the monitor I was fooling around with

A local school has apparently been having problems with vandalism lately. Apparently some troubled high school kids have been waving kitchen magnets over a few monitors, breaking the monitors. Any good articles on how to demagnetize the monitors?

 

[tokala]

http://www.wikihow.com/Degauss-a-Computer-Monitor

The "rigged power drill" method worked in my case. I was using a pretty hefty NdFeB "supermagnet" though, no idea how well this works with "lesser" magnets.

 

[Skwink]

My Macbook is held closed by a Magnet.

 

[aimeeandbeatles]

Some monitors have a built in degasser. Id try that a few times before messing around with anything else.

When I said "rare earth magnet" Im not sure that was the right term. It's what it says on the case.

A book I have claims that in the center of one of the older 5 1/2 inch floppy disks was a spot where you could stick a (fridge) magnet without any damage. I don't know if it's true or not and Im not sure where the book is at the moment.

 

[Genocidicbunny]

That would be degausser. A Gauss is a measure of a magnetic field, so therefore it would sort of make sense to call a degausser that. A Degasser on the other hand...sounds like something you take to get rid of gas.

 

[Turner]

I need a degasser..... Was that TMI?

I think it's pretty interesting that the hard drives have extremely powerful magnets in them, and virtually no field outside of the unit. I've taken several apart to farm the magnets, and it amazes me how such a strong magnet can be 'blocked' by a little piece of metal....

 

[aimeeandbeatles]

Speaking of magnets, how susceptible are cassettes to it? Is there anything special you should do when you put them in a box? (other than avoid putting magnets in the same box)

 

[B-29 Bomber]

How about EMPs(electromagnetic pulse)? Don't they screw up microchips and the like? That's why Sci-fi writers have the alien invaders detonate a nuke in the atmosphere to disrupt communications, such as in The Worldwar series by Harry Turtledove.

 

[Narnia]

How about EMPs(electromagnetic pulse)? Don't they screw up microchips and the like? That's why Sci-fi writers have the alien invaders detonate a nuke in the atmosphere to disrupt communications, such as in The Worldwar series by Harry Turtledove.

Yes and no. Yes, they do mess up electronics, but no, it is a different mechanism than what you have to worry about with kitchen magnits and the like. I think (highly stess the word think) that they somehow generate electricity in wires (much like how a generator works) and that power surge is what kills. Please however note that I reserched this several years ago, didn't fully understand it then, and my primary source was wikipedia so there is a good likelyhood that I am wrong.

 

[Genocidicbunny]

An EMP creates a rapidly fluctuating electric field, which in turn results in a changing magnetic field, which can induce current in conductors. This current may be above what that conductor can deal with, which results in it essentially burning out.

 

[Souron]

More damaging than current in conductive wires are random currents in transistors and capacitors which can have much lower voltage tolerances, particularly if they get revered polarized.