Main > Main Forum
Will a standard subwoofer magnet wreck havok on my PC?
Darkstalker:
"it will only react with the HDD if it is moving. Since the magnet in the speaker doesent move, it will do no damage."
Umm...what? You do realize that a magnet constantly exerts force lines between the north and south poles and they are what cause the damage to magnetic sensitive equipment, right? It has nothing to do with movement...
"The electromagnetic coil on the speaker might cause problems, but consider this: the little unshielded PC speaker has been sitting about 2" from my high speed/capacity drive for over a year, and I have not noticed a single problem."
The coil magnet in a 2" speaker doesn't have enough field intensity to do any damage unless it's in very close proximity to your hard drive. The coil in a sub, however, will be much larger and more hazardous. I've lifted 20 pound weights using a 10" sub coil magnet.
"Also, is your computer in it's case? Is it metal? If so, this should protect it just fine."
Actually, a PC case being metal will more than likely extend the magnetic flux due to magnetic induction than protect the contents. Depends on the strength of the magnet to determine the amount of risk.
In short, keep magnets away from anything sensitive to magnetic induction (i.e. CRTs, and magnetic storage media). The stronger the magnet, the more space you need. 3.5' should be fine from your monitor, but your PC may be a different issue.
Trimoor:
--- Quote from: Darkstalker on August 09, 2004, 02:42:32 pm ---Actually, a PC case being metal will more than likely extend the magnetic flux due to magnetic induction than protect the contents. Depends on the strength of the magnet to determine the amount of risk.
--- End quote ---
What do you think shielded speakers are? It's a metal box around the magnet/coils.
And don't forget that the HDD itself is enclosed in a thick metal box.
Also, a non-moving magnet will do no harm to a CRT. Really. If it causes the colors to swirl, just degauss it, that will reset the magnetism of the shadow mask to compensate for the magnet.
Ever got one of those old AOL floppies in the mail? I got bored one day and took a HDD magnet (the super powerful rare-earth type) and started rubbing it along the floppy. I did that for about 20 minutes, and it was still able to read it perfectly. (no, I did not install AOL!)
--- Quote ---Umm...what? You do realize that a magnet constantly exerts force lines between the north and south poles and they are what cause the damage to magnetic sensitive equipment, right? It has nothing to do with movement...
--- End quote ---
Wow, you must have flunked physics...a magnetic force acts upon an object ONLY when it is moving perpendicular to the magnetic field. (if the object is moving at an oblique angle, only the perpendicular vector of the motion acts upon the object.)
electricd:
whoa...there is some serious flux capacitor language in here! :)
Trimoor:
--- Quote from: electricd7 on August 09, 2004, 03:33:39 pm ---whoa...there is some serious flux capacitor language in here! :)
--- End quote ---
HEY, WATCH IT! Do you want to get sued?!? :o
It's "delux capacinator" language. ;D
Darkstalker:
"What do you think shielded speakers are? It's a metal box around the magnet/coils.
And don't forget that the HDD itself is enclosed in a thick metal box."
It's an alloy placed around the magnet. In the strictest sense, magnetic shielding isn't actually shielding at all. Magnetic shield materials create an area of lower magnetic field in their vicinity by attracting the magnetic field lines to themselves.
"Also, a non-moving magnet will do no harm to a CRT. Really. If it causes the colors to swirl, just degauss it, that will reset the magnetism of the shadow mask to compensate for the magnet."
Given the fact that we're talking about relatively small magnetic charges, I agree. If it's a strong enough charge to pull the electron beam inside the CRT and distort the image, that's a different story. Even at 3.5', a spot will most likely appear on the lower part of the screen
"Wow, you must have flunked physics...a magnetic force acts upon an object ONLY when it is moving perpendicular to the magnetic field. (if the object is moving at an oblique angle, only the perpendicular vector of the motion acts upon the object.)"
You're right, my appologies. I must have been thinking more in the terms of electromagnetic forces. BUT, instead of discussing the finer nuances of Lorentz law and magnetic and electromagnetic forces and fields and getting way more complicated than this needs to be, I'll leave this last thought to this thread:
It is better to be safe than sorry.