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We see in Movies and TV Shows that electricity and water don't mix. And when they do, fatal results take place.

But I've heard that this is only an exaggeration for the dramatic effect. I've read a story about a person who immersed live electric wire into a bath tub while he was in it, and nothing happened. If I remember correctly: "water has too much resistance to current". The experiment was done in a tub, let alone a large swimming pool, where, if the same logic applies, no one will feel any difference.

Edit: i am not talking about dropping appliances into water. I only mean stripped wire (copper) immersed directly. See below for reference:

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    I really, really would advise against testing this in person... – Walt Dec 3 '15 at 6:40
  • "water has too much resistance to current", What? – Ankit Sharma Dec 3 '15 at 6:45
  • @Walt I have edited my question to clarify the common misunderstanding. Please see update – Ahmad Dec 3 '15 at 10:10
  • @AnkitSharma i updated my question. Please take a look – Ahmad Dec 3 '15 at 10:10
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    @AnkitSharma, Statements like that stem from the fact that pure H2O is a terrible conductor of electricity. In the real world, we rarely ever come in contact with pure H2O. There's always dissolved salts or minerals in the water that make it a pretty good conductor. – JPhi1618 Dec 4 '15 at 15:34
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No, it is not a myth. Electrical shock can occur and can be lethal. As @Sanpaco has linked, it has been empirically proven by the Mythbusters, while it has been anecdotally proven by various - incidents - in - the - news.

By code, most if not all bathroom tub and shower and pool pipes are electronically grounded.

Yes, movies and tv do exaggerate how that death happens. In film and tv, death by electrocution in water is very violent, boiling the water and the body flailing. In reality, it does not take much to short circuit the heart, and any constant current through muscles will lock them up. Look at taser videos to see how the body would react.

Dropping a live appliance into a bathtub would result in a direct short to ground. Water, while not a perfect conductor, is a good conductor. Salt water is much better, but 120 to 240 mains voltage will breakdown in water and cause a significant short, compared to the amount needed to stop the heart.

This link is a Google Books copy of Electrical Injuries: Engineering, Medical, and Legal Aspects By Robert E. Nabours, Raymond M. Fish, Paul F. Hill, The linked section describes the forensic history of a bathtub electrocution case. The short of it was that a hair dryer, dropped in a bathtub that was electrically isolated from ground, caused the GFI or GFCI not to trip, resulting in more than 5 milliamps to soar through a women, killing her.

Slightly unrelated, but still important, even a 9 Volt battery can kill, in the right conditions. Surface Skin resistance is fairly high, (500KΩ to 2MΩ), but break the skin, or go through the other bodily openings and the salty and high electrolytic content of the inner body will cause you to die from a 9V battery.

  • I agree about dropping appliances into water, but what about if naked wire is immersed directly into water? – Ahmad Dec 3 '15 at 10:02
  • A single live wire, with a grounded pipe, will conduct. A GFCI will trip, but sub par electrical will cause a significant current to flow. Oddly enough, a single bare conductor with no ground will NOT cause electrocution, as no path or circuit is created. @Ahmad I would still not play with bare wires. – cde Dec 3 '15 at 11:35
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The myth from movies is the violence and prolonged electrocution, not the fact that its possible to be electrocuted. By the National Electric Code, any electricity close to water (pool lights to outlets in a bathroom) must be protected by devices designed to detect shorts (being overly simplistic here) and cut power to prevent electrocution.

In most cases, any "live wires" in water would immediately (on the order of a few milliseconds) trip the current protection device and no harm would be done to anyone other than maybe a slight jolt. That said, the few milliseconds of current can kill in the right situation so it's never safe to try this, but it's certainly rare by design.

There are certain failure modes that can cause actual electrocution, but even then it would be quick and largely silent. Any scene in a movie where someone is electrocuted violently for several seconds would have to be caused by a failure of 3 or more protection devices with wires the size of jumper cables being used in place of the typical "lamp cord".

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