Re: Power Lines

[Rick Tarara <rtarara@SAINTMARYS.EDU>]

Tina,

Think POTENTIAL DIFFERENCE here.  The single line may be at 100,000 Volts
relative to ground, but the current that runs through you will depend on the
PD between your hands (hanging) or feet (standing).  Is there a PD?  In most
cases no.  The danger with people and power lines is that we are big enough
to easily come in contact with TWO lines--two lines at different potentials
and therefore a significant PD.  The birds are small and will seldom, if
ever, contact two wires at once.

Rick

*********************************************************
Richard W. Tarara
Professor of Physics
Saint Mary's College
Notre Dame, Indiana
rtarara@saintmarys.edu
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Free Physics Educational Software (Win & Mac)
www.saintmarys.edu/~rtarara/software.html
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----- Original Message -----
From: "Tina Fanetti" <FanettT@WITCC.COM>
To: <PHYS-L@lists.nau.edu>
Sent: Tuesday, February 25, 2003 12:01 PM
Subject: Power Lines


> 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...
> He then asked if he stood on the power line, like a bird, would he get
electrictuted.
> I was like what kind of an idiot would want to stand on a high pwer
line....(okay maybe not so tactful)
> But would you get electricuted?
> I would think that if the current went foot-to-foot you would be okay, but
who really wants to take that chance?
> 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