micky
Tue, 07 Mar 2017
21:29:46 GMT in alt.home.repair, wrote:

Why do laptop power supplies, the ones with black rectangular
things in the middle of the cord, have 3-prong plugs when
everything you can touch is plastic or "rubber"?

Filtering perhaps? Limited surge supression components? Redundant
safety...I've got a few laptops around here that have the 3 prong and a
couple that don't. I prefer the ones that dont, because, sometimes, the
3 prong ones generate unwanted background hum when fed to external
audio amplifiers while plugged into their chargers.




--
Sarcasm, because beating the living **** out of deserving people is
illegal.