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"?
And, I believe, when there's nothing more dangerous than a lamp
underneath the plastic and the rubber?


If the power supply were to short power could get through the
laptop, and out the USB or headphone, or whatever jacks.?
Anyway, some require grounding by code, others don'r.


Many manufacturers put an IEC socket on the laptop power supplies because
the power supplies will operate on multiple voltages. It's simple to change
the cord that's shipped with the laptop depending on the area of the world it's sold in.
It's the same with desktop computers. If the computer is shipped to a part
of the world that uses 220vac 50hz, all you do is use a power cord that has
the appropriate plug. t(?)_/¯
[8~{} Uncle Power Monster


My Lenovo laptop has a 2-prong plug and the converter
is rated for 240 volts. I guess I am in mortal danger -
if "the power supply were to short" ... :-)
John T.