Re: Power Lines

[Herbert H Gottlieb <herbgottlieb@JUNO.COM>]

On Tue, 25 Feb 2003 11:01:08 -0600 Tina Fanetti <FanettT@WITCC.COM>
writes:
> Today in class, we were talking about why birds standing on power
> lines don't get electrocuted.
>
> One of my students asked if he grabbed on to a power line would he
> get electrocuted.. yes, because the current would flow through the
> chest and could stop his heart...

*** No he wouldn't get electrocuted any more than a bird would. There
must be
 a potential difference across his body for current to flow.
It is the same effect as putting your finger into only one opening of the
wall
socket of your living room (without your being grounded at the same time)
> He then asked if he stood on the power line, like a bird, would he
> get electrictuted.

*** No problem here either. However, he would have a problem if he tries
standing on a power line like a bird!

> I was like what kind of an idiot would want to stand on a high pwer
> line....(okay maybe not so tactful)0
> But would you get electricuted?

*** You would get the same sensation as the bird....Nothing!


> I would think that if the current went foot-to-foot you would be
> okay, but who really wants to take that chance?

*** It's done every day.   I once tried standing on the third rail
of the exposed track of the Long Island Railroad here in New York.
I was very careful to get both feet on the track at the same time.
Now, 70 years later, I'm still here to tell about it.  Try it Tina.

Now, just for the hell of it, with the lamp in your living room unplugged
from the wall, cut the wire off and scrape off the insulation
from one of the two leads at free end. Be careful that the bare end of
the other lead is covered with tape.  Now put the plug back into the wall
and touch only the
exposed lead with your right hand.... NO SHOCK!   Try touching that same
lead
with both hands at the same time..... NO SHOCK!   It's the same as trying
to light a 120V electric bulb with only one connection to the bulb.

Are you willing to bet your life on the theory that you teach???
I am!

Herb



> Thanks
> Tina
> PS I did search google....not finding anything useful yet...
>
> Tina Fanetti
> Physics Instructor
> Western Iowa Technical Community College
> 4647 Stone Ave
> Sioux City IA 51102
> 712-274-8733 ext 1429