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So, I'm sitting here looking at a chewed up extension cord that I just unplugged from the wall out of fear. Both the neutral and hot sides (no ground) have been chewed to (and part way through) the bare copper. My rabbit is nuts, I know, but did she really continue to chew while receiving 120 volts AC for her trouble? This is throwing everything I thought I knew about electricity into a tailspin. Maybe she wasn't grounded well, but I've been shocked myself when I was probably less grounded. Any help greatly appreciated!

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    \$\begingroup\$ It's just a phase she's going thru. don't worry so much. Rodents love PVC so much. It's like candy \$\endgroup\$ – Sunnyskyguy EE75 Jun 5 '17 at 5:21
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    \$\begingroup\$ Emergency. We need a moderator here to sinbin Tony Stewart for that pun. Good lord the pain. \$\endgroup\$ – replete Jun 5 '17 at 5:25
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    \$\begingroup\$ the calcium content must be a low permittivity insulator in a low sodium saliva and Bugs might say to the coronor, What's Up Doc? and he would reply. You Wascally Wabbit now wook what you done. the chinese will dwop ivory tusks and think wabbit teeth give immotality \$\endgroup\$ – Sunnyskyguy EE75 Jun 5 '17 at 5:38
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    \$\begingroup\$ assuming the rabbit chewed with its front teeth, it was probably ok by luck of its anatomy. Look at a rabbit's jaw: the front teeth are well ahead of the tongue and molars. the "lips" in front are dry and hairy, not a good conductor. so as long as it didn't get the wet part of the mouth on the wire, shorts are more likely to self-dissipate than fry your rascally wabbit. \$\endgroup\$ – dandavis Jun 5 '17 at 6:41
  • \$\begingroup\$ @replete: 120VAC so most likely US. Ain't no wall switches on the outlets. \$\endgroup\$ – JRE Jun 5 '17 at 7:36
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Why did the rabbit leave the cable alone after a while? Perhaps she did receive a tingle.

Teeth have a high resistance. It's unlikely a fatal current could flow through them. A fatal scenario would need the rabbit to be well grounded at a remote body point, and to be contacting the bare live with lips or tongue. Contacting both live and neutral with lips might leave a burn (and be very educational for the rabbit) but be unlikely to kill.

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  • \$\begingroup\$ my tongue can measure the difference between 1V and 1.6V from a new cell due to Ohm's Law, whereas my fingers cannot even sense -48V so I guess Phil's Wabbit must have a dry mouth. I even have my fingers calibrated in pF \$\endgroup\$ – Sunnyskyguy EE75 Jun 5 '17 at 5:44
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The short circuit would have been, well, short, and not through a critical, electrically sensitive organ like the heart. The rabbit may have felt a shock, tingle, burned fur or flesh or other effect but that does not necessarily mean it was safe. That it did not die is simply one outcome of chewing on electrical cords.

Keep in mind, that while the conductors may have been exposed, unless they were shorted out with something like spit or flesh, mains voltage is not high enough to conduct across a nominal air gap.

Aside: My old electronics teacher in high school used to tease us with touching mains voltage between two fingers on the same hand. Due to skin resistance and the non-harmful path, this is technically safe, but I still didn't want to risk it, even knowing the science behind the trick.

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  • \$\begingroup\$ Please never try to touch AC mains, from personal experience I can assure you that it can leave you with serious skin burns. The teacher's experiment may work with dry hands, but as soons as they are a little sweaty the resistance increases dramatically! \$\endgroup\$ – Humpawumpa Jul 2 '18 at 5:40
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    \$\begingroup\$ @Humpawumpa Do you mean "decreases"? \$\endgroup\$ – Joel Reyes Noche Jul 2 '18 at 5:44
  • \$\begingroup\$ Sorry, sure I do :) \$\endgroup\$ – Humpawumpa Jul 2 '18 at 5:47
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Common misconception. Touching mains isn't 'automatic death'. It's Russian Roulette.

Several factors have to converge in order for it to kill you (or not kill you). One is skin conductivity (conductance is 1/resistance). Another is how much current flows and each of the different routes through the body. Current follows all parallel paths in proportion to their conductivity. (And now the paralleling resistors formula may make more sense, you are simply adding the conductivities).

Obviously, good practice and use of PPE (such as GFCI/RCBO) can control those factors nearly 100%, that is their job.

But a lot of electrocutions are wildcard situations like finding (or gnawing) a point of failed insulation, using a landscaper's bucket truck (which isn't insulated) too close to distribution lines, etc. In these wildcard situations you just can't control enough factors, and that's what makes it Russian Roulette.

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protected by Tom Carpenter Aug 21 at 8:23

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