Re: [Phys-L] electric shock

[Daniel MacIsaac <danmacisaac@gmail.com>]

I like #1 and would add direct destruction of skin tissue.  If you draw a
VdG spark to a key you can see pitting, metal vaporisation and erosion
on the key tip surface.  Though the ionic slime in skin sweat and in 
your blood may dissipate this enough to avoid for healthy skin.

Also the sudden muscular twitch can be painful.
I have not hear of anyone seriously injured with a classroom VdG,
surprisingly.  Though I do ask folk with pacemakers or holding 
sharp screwdrivers and knives or balancing on stools to keep back
as I do worry about sudden uncontrolled muscular twitches.

Dan MacIsaac, Associate Professor of Physics, SUNY-Buffalo State College
462SciBldg BSC, 1300 Elmwood Ave, Buffalo NY 14222 USA 1-716-878-3802
<macisadl@buffalostate.edu>  <http://PhysicsEd.BuffaloState.edu>
Physics Graduate Coordinator & NSF Investigator for ISEP (MSP) and Noyce

On Aug 17, 2015, at 10:50 AM, Carl Mungan <mungan@usna.edu> wrote:

> A colleague of mine asks why an electric shock hurts? Specifically we were thinking of an electrostatic spark, such as when you rub across carpet and touch a door knob, but a more general answer about other kinds of dc and ac electric shocks is also interesting.
>
> We brainstormed three possibilities in what we think is in order of decreasing likelihood:
>
> 1. Some directly electrical effect such as an electrostatic force on the atoms of your finger or even directly acting on the ions in your nerve channels.
>
> 2. A thermal effect of the hot “mini lightning” strike.
>
> 3. An acoustic effect as a “mini thunder” pressure wave hits your finger.
>
> Can anyone shed any light on the question?
>
> -----
> Carl E Mungan, Assoc Prof of Physics  410-293-6680 (O) -3729 (F)
> Naval Academy Stop 9c, 572C Holloway Rd, Annapolis MD 21402-1363 
> mailto:mungan@usna.edu     http://usna.edu/Users/physics/mungan/
>
> _______________________________________________
> Forum for Physics Educators
> Phys-l@www.phys-l.org
> http://www.phys-l.org/mailman/listinfo/phys-l