Newbie that don't understand

[Peter Hansen]

Just a dude wrote:
> 
> >how can 23 and -23 be equal?
> >
> To some this can be a hard concept to grasp. 

I can't grasp it either, because it's not possible.  Only their absolute
values are equal, not the numbers themselves.

If the answers were unclear, it might be because we aren't sitting
face to face reading body language and seeing confusion on your face.
The Usenet medium can require a couple of abortive attempts before
an answer works, as we experiment and try to find the proper level
and manner of replying.

> My son is an electronics
> design engineer, and I still can't get my head around negative
> voltages, how the hell do you get a -12 V supply... to him it's basic
> but to me..............

With a 12V supply, the power supply is trying to push electrons
out the negative terminal and into the positive terminal.  If you
have a -12V supply, it tries to push electrons out the positive
terminal and into the negative terminal.

-Peter