Magnet Strength & Computer Safety: Debating Teslas

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The discussion centers on the potential harm magnets can cause to computers, specifically regarding the strength of magnetic fields measured in teslas. A .155 Tesla magnet, used in a lab setting, is considered insufficient to damage a computer, as the induced currents from smaller magnets are minimal. Modern computers are equipped with protection networks that can handle high voltages, making them resilient to such magnetic influences. Hard disk drives are only vulnerable to very high flux density fields and require the magnet to be extremely close to pose any risk. Overall, the consensus is that typical magnets, even when waved near a computer, are unlikely to cause harm.
derekmohammed
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Hi,
My friend and I were arguing about this the other day and I wanted some input from you guys:

How many teslas would it take to potentially harm a computer. In the lab we use a .155Tesla magnet to move encased objects around in our rutherford scattering lab. I said that the magnet was not nearlly strong enough to harm a computer even if you put it right on its caseing. He said that even small magnets like fridge magnets could potentially harm a computer if waved around the caseing. He said the induced current would damage transformers. I differed saying that the induced current would be much to small and would have little effect even from the bigger 0.155 tesla magnet we were using.

Thanks for your input!
 
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1) Computers don't have many transformers. The power supply has at least one, but that's about it.

2) The induced currents caused by waving a magnet at a computer are incredibly tiny, and all modern integrated circuits have protection networks that can withstand kilovolts without damage. No problem there.

3) Hard disk drives and other media are vulnerable only to very high flux density magnetic fields, and only in certain orientations. The read/write head in a disk drive is very small and very very close to the disk surface, enabling it to create very high flux densities when writing. You'd have to get your magnet extremely close to the disk to create any real threat.

4) Finally, the most sensitive components in a computer are heavily shielded, and you'll just be inducing currents on the outside of the shield material.

- Warren
 
Thanks for the quick reply,

That is what i thought! The flux from the magent would not be nearly enough to do any damage. Thanks!
 
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