alt Hacker NewsThey can’t, it’s caused by the capacitors required to suppress electromagnetic interference caused by the switch-mode power supply. These allow a very very tiny amount of current to leak through from the mains side, which is then capacitively coupled to the metal case (IIRC Apple do not connect the case to power negative) reducing it further, but it’s enough for humans to sense it.
It can be avoided by using a grounded power supply, but because there are large countries that have ungrounded outlets in common use the most designs are ungrounded.
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Why do only Macbooks suffer from this problem? When I had a work-issued Macbook I charged it and my personal Framework off the same USB-C charger and I only every felt the leaking current from the Macbook
I once had an HP with an aluminum case and it had a grounded power supply but if you plugged it in without grounding his an adapter (sometimes you gotta do what you gotta do). You could feel it straight up vibrate while conducting current if you rubbed your hand over it. Not enough to shock me but it felt like kind of a shoddy design and leaked a lot more current than I've felt on a MacBook.
Thank you for explaining this! I've been feeling this on my girlfriend's macbook for years and I've always wondered what the hell that was. :D