Question

in terms of physics how can a magnet damage a laptop such as hard-drive, cpu, motherboard etc.

Answer 1

Yes, a magnet can destroy the hard drive inside a PC, but you need a much stronger magnet. The worry here is that magnets can delete the information stored on your hard drive. Because of how hard drives work, magnets won’t delete anything from your hard drive. Your hard drive has a very powerful magnet inside that controls the read-write head movement. If the magnet inside the drive itself doesn’t delete information, any magnet that isn’t insanely powerful won’t wipe it either.

While a magnet isn’t going to wipe your hard drive, if you leave a powerful magnet directly on top of your hard drive there is a slight chance that it could cause damage to the hard drive itself while it’s functioning.

An EMP (Electromagnetic Pulse) may destroy the information contained in your hard-drive or can destroy cpu and motherboard. But a medium sized magnet can't do that. We need a really strong magnet to damage a laptop.