On Thursday, March 23, 2017 at 4:02:39 AM UTC-5, Jon wrote:
On 03/22/2017 04:28 PM, Micky wrote:
Why do they have a 3-prong plug on the power supply for the laptop
when all the surfaces are plastic or rubber? It couldn't be for
parts beyond the black box becasue the wire from the box to the laptop
is just two wires.

Is it just to make people who are afraid of computers and elelctricity
be less afraid?

Just a wild guess but maybe some sort of built-in surge or over-voltage
suppression?


It's more than likely there to shunt the electrical noise to ground that's produced by the switching power supply. Another thing is that the power supplies are made to meet the specifications of multiple jurisdictions and have an IEC connector which has a ground/earth connection and works with different power cords and voltages. Every laptop I have including my Chromebook operates on 19 volts DC and uses a switching power supply which must meet FCC specs for RF interference. If you have a little pocket AM/FM radio, switch it to AM and place it next to a plugged in laptop power supply and hear the noise. There is also the problem of ESD,"Electrostatic Discharge" that grounding can help control. Anyway, there are some good explanations to be found on The Interweb. ヽ(ヅ)ノ

http://electronics.stackexchange.com...apter-grounded

http://tinyurl.com/k2w4vbb

[8~{} Uncle Power Monster