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Comment by egdod | Hacker News Reader

Sounds like a coincidence.

It does sound that way but, boy, it was eerily timed if it was.

Magnetic field falls off with inverse cube of distance once you're past the approximate size of the magnet. Not to mention that the drive itself is in a ferrous enclosure that provides a lot of shielding... the magnetic field you applied at 6 inches is approximately nothing.

I will definitely concede that I may have the 6" measurement wrong. Heck-- I may have actually put my hand right on the PC.

I stack running hard disk drives, all of which have large neodymium magnets inside them, in close proximity all the time with no ill effects. It makes no sense.

Isn't it inverse square?

No. Magnetic fields fall off as 1/d when d is small compared to the size of the magnet, progressing to 1/d^3 when d is large compared to the magnet. (E.g. weird edge case-- it's inversely proportional to distance from an infinitely long wire).

Electromagnetic radiation from point sources falls off as 1/d^2.

Thanks a lot, both of you, learned something!

No, it’s a dipole moment instead of a monopole like electric charge. It goes as 1/r^3 in the far field.

I'd bet on related, but not what you thought. If I had to guess, I'd put my money on the magnet pulling some tiny metal bits into the control board and shorting it.

But one thing is for sure. OnTrack are dicks. Can confirm.

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