James Bond physics question.

[Brad Buchanan]

OK folks this is in reference to the Bond film in which he dispatches a henchman by throwing an electric heater into a bathtub containing said henchman and water.

Question is: If a person is seated in a bathtub full of water and an energized electric appliance falls into the tub with him will he or she be electrocuted?

Question assumes the appliance does not touch the person and nothing is added to the water.

Brad

 

[John730D]

Yes, friend of mine was killed when a radio fell in the tube.

 

[pburchett]

Yep! Electrocution Time!! Ionic compounds in the water will conduct electricity. Ionic compounds could be soap, chlorine, calcium from stone, iron… PURE water does not conduct electricity, but good luck finding water that is that pure as the cleanest rain or distilled water does not qualify as it will dissolve compounds out of the air or out of its container.

 

[Dusty MI]

Depends on how the tub is plumbed.
If plumbed with PVC or PEX, I would say no.
If the water is pure water without any iron in it, like distilled water, not to likely.
If plumbed with copper or steel pipe and common well water with iron and lime etc. in it. Quite likely.

 

[old]

If the tub is a metal one and has a good ground then not likely due to the fact electricity takes the path of lease resistance but if not grounded the person may be ok as long as he does not touch a ground.

 

[Martin Reece]

Yup, when i was a kid, my friend died when the hair dryer fell in the tub.
Martin

 

[Stan in Oly, WA]

Hey Brad,

Two of the five people who have responded before me know someone who died when an appliance fell into a tub (or possibly a tube) they were in. It's hard to argue theory against flat out facts. But it's never made sense to me either. Neither of the two possible situations, a metallic tub plumbed with steel or copper, or a non-metallic tub plumbed with plastic, make it clear to me why a human body, which is a fairly poor conductor, would get some of the current running through the let's say dirty water, which is a better conductor. And if the body does become a conductor, what would make the current run to the upper body where the heart is when that part of the body is not in the water.

If a plastic tub got its water through CPVC and drained it through ABS, where would the electricity go if an appliance fell into the tub? To be killed by conducting electricity, don't you have to actually conduct it somewhere, not just load up more and more of it into your body?

I looked this up on Mythbusters on You Tube a few weeks ago, but the answer was ambiguous. Also, I once asked this question to an electrician I was on a job with, but he was no John T, to put it mildly. So I feel like I'm still waiting for an explanation of how it can happen.

Stan

 

[buickanddeere]

As long as a current path of 30-50 milli amps passes through the breathing and heart muscles.
Of course both the gfi receptacle tripping and the receptacle being located more than 4-1/2ft from the tub would prevent the incident.

 

[Steve A W]

Read this article about the Guy trying to charge His boat battery.

Steve A W
Tragic

 

[Leroy]

If the water came into your hose it stiil would be connected back somehow to an Iron fitting that would be grounged, even a pump, and the current could flow miles to find that ground.

 

[gtractorfan]

That also reminds me, how can a person touching a wire fence be electrocuted in a lightning storm when lightning strikes fairly far away? The fence is grounded all over the place in contact with the ground and metal posts.

 

[Indiana Ken]

(reply to post at 16:25:30 08/04/13)

I suspect my (and others) first response would be to pick up whatever electric device fell into the tub and throw it out. In that case you would be in contact with the device and likely to be part of a circuit to ground. In the case of the man killed charging the boat battery the article stated he was holding the battery charger as he fell into the water, reference previous post.

Your question specified the victim can not touch the device. Therefore, to be electrocuted there must be a circuit to ground present in the water. The persons body must be: 1) between the voltage source and ground, 2) his/her body must have a lower resistance to electrical flow than the surounding water. If these two conditions are met, then I would maintain it would be possible for an electrocution to result.

I feel one would be safer in salt water than in fresh water. Perhaps the next movie will have the roles reversed....James Bond saves himself by adding salt to the water before taking his bath.

 

[Hal/ Eastern WA]

I think a human body would be a reasonably good conductor, since most body fluids are ionic solutions. Dry skin is probably a lot poorer conductor, but if you are sitting in water, the skin would be wet.

We were always taught that electricity will follow the path of least resistance. I suspect that a human body, sitting in water would be less resistant than just the water. And if applied correctly it doesn"t take much electricity to really mess up the internal electrical signals in the body. Maybe causing heartbeat timing issues or nerve impulse disruptions.

It is an interesting idea to consider the impact of plastic plumbing, both supply and waste on this question. It would seem that if the supply water was not on at the time of the electric appliance going into the bathtub, the only pathway to ground would be through the dampness clinging to the insides of the waste piping. I wonder, but sure not enough to test the theory out!

 

[Stan in Oly, WA]

This is nit picking, but I want to be right about something on this topic, and I'm not doing too well so far. Anyway, the article you included the link to said that both the brother and sister were electrocuted, but she survived. If she survived then she wasn't electrocuted, only shocked. Electrocution means to die from electricity. On the other hand, I have to admit that words mean what people think they mean. If everybody decides to use it to mean shocked, then pretty soon dictionaries will start defining it that way, and when I disagree with someone about it and look it up to support my point, I'll find out I'm wrong.

Stan

 

[Anonymous-0]

I think it's highly probable. I was fixing a leaking irrigation line at a gold course and when I went to jump in the hole, I put my hand down and got a shock. I was holding the stinger from the welder but never touched the ground cable at all. The ground was so wet from the leak that the area around the hole was "live".

 

[paul]

Water is a conductor itself, and it makes your skin, normally a pretty good insulator, into a good conductor.

I think those things don't answer your question, but they sure add in to the whole deal.....

Of course, if you throw an electrical device into the water, you are supplying both a live and ground wire so the circuit can be made. Water flows electricity kinda weird, so it flows out and around all the water, not just the shortest distance from the hot to ground wire.

I don't suppose you ensure death, but it seems a good possibility of it exists.

Paul

 

[Geo-TH,In]

Just a thought. What if the tub were fiberglass, an insulator, and all the plumbing were plastic?

Yes, the GFI will save him.

 

[Bus Driver]

Pure water is a rather poor electrical conductor. Many things found in water make it a better conductor.
The possible penalty makes it foolish to take a chance.
It takes only a small electrical current, about 1/10 the amount to light a 100 watt bulb, to kill a person.

 

[big fred]

Humans conduct better than fresh water, so the current will pass thru the body instead of the water. If the tub was filled with seawater he would be less likely to be electrocuted.

 

[glennster]

here is an article about some teenagers who were electrocuted while de-tasseling corn a couple years ago. there was a center pivot for irrigation in the field. something was wrong, and the kids were electrocuted. would not of thought this could happen.
poke here

 

[buickanddeere]

Just for the record we circulate de ionized water through the stator bars in the main generators for cooling. 24,000 volts and 900 Mega watts

 

[mkirsch]

Mythbusters did an episode on this in 2004. You can see them re-create the circumstances and measure what happens.

As I recall they had a difficult time getting it to happen, but they did eventually manage to electrocute their "victim."

It requires a very specific set of circumstances but it is possible.

 

[JMOR]

(quoted from post at 10:17:42 08/05/13) Just for the record we circulate de ionized water through the stator bars in the main generators for cooling. 24,000 volts and 900 Mega watts

ithout specific knowledge of the exact implementation, that statement means zero. Could likely be done with very little voltage gradient across the water.

 

[Geo-TH,In]

Wow, never heard of de ionized water, is it distilled? How do you do that? How do you keep the water from picking up ions, metal particles from the pipes? That would have to be ion free to with stand 24000v. Will reverse osmosis remove ions?

 

[Bob M]

Yes. Sadly I lost a cousin to electrocution in exactly that matter.

Electrical appliances and water are a deadly combination!!!

 

[BIG RUH]

A lot has to do with what type of tub. If it's plastic or fiberglass, it will be a lot harder. Cast iron will be more doable.

 

[Bob]

A cast iron tub would be ceramic-lined, making it pretty much insulated like a plastic or fiberglass tub... neither YOU nor the water would be grounded, but imagine what happens when you touch the grounded metal faucet!

APPARENTLY, like the Busters found, it's difficult to do, which is NO consolation to anyone who has lost a loved one in a RARE case where electrocution happened!

 

[buickanddeere]

Lake water is filtered in several stages then polished in
positive and negative ion columns until the water is only a few
parts per billion purity. Same stuff that is feed stock for the
boilers.
The main generator stator bars are are hollow. To cool the
stator bars . Cooled demineralized water is pumped through
the stator bars. The stator cooling water has a portion of the
flow pumped through ion columns to keep it pure.
Even with 24,000V the electricity does not flow through the
pure water.
What is it with you guys that don't believe me about well
known technology that has been in use for 7+decades.

 

[Greenday]

I'm more worried about why he wants to know! lol

 

[Geo-TH,In]

I believe you, just never seen or heard of it. I also thought the water was in contact with the wires. I see better see what you are talking about and it's very interesting.

 

[Brad Buchanan]

Hey Stan,

I am no engineer and I don't profess to know if a person would be electrocuted.

However... I can speculate that of the persons body did not touch the appliance or cord there would be no 'path' through the body, kind of like a bird sitting on a high voltage wire.

Anyhoo thanks for the reply. It is interesting to see people exercise their minds on an abstract problem.

Brad

 

[Brad Buchanan]

Thanks all for the interesting and provocative posts.

It never ceased to amaze me the amount of knowledge and expertise available in a group of old tractor buffs like myself.

And by the way I am not going to try this experiment on myself. But if I did I would surely post pics.

The thoroughly desiccated Brad

 

[TomH in PA]

All the discussion about whether fresh water will conduct electricity or not is moot.

As soon as the person sees the appliance fall into the water the person will lose control of his/her bladder...

 

[dr sportster]

You'll get caught like that. Think more of a boating accident . " I told her to get me a beer in the back of the boat and I turned around and she was gone".

 

[Rich_WI]

The tub, the drain or the fixtures will need to complete the circut or nothing will happen. It could also be said that the tub, the drain or the fixtures would have to provide an alternate path to ground or nothing will happen. Example: substitute the tub in your question for an insulated rubber tub. Now drop the electrial appliance in it. There is only one way for the electricty to go in and one way out.... through the wires. With the insulated rubber tub, the person is safe.

I was in a safety class where the instructor demonstrated the above example using a hair dryer, a GFCI and a rubber tub. Everybody thought the hair dryer would fry and short out, much like is shown on TV. It didnt, it started pushing water around like a motor boat (weird to see that). The class also thought the GFCI would trip to shut the hair dryer off, it didnt because the only way for electricty to go in and out was the cord, GFCIs trip when 5 miliamps turn up "missing". Finally, the instructor reached his hand in the tub and retreved the hair dryer, no shock or nothing. He could do that because he was standing on an insulated rubber mat. Had he not been doing that, he risked a shock but on the mat it prevented electricty from taking a short cut to ground, just like a person in a tub would stay safe.

It was a good class, I learned alot. The instructor really drew the class in and made everybody think by demanding an answer of what would happen when he did something. Then almost universally he proved everybody wrong and taught the class the proper answer through a demonstration that he explained. The instructor would have made some serious cash if he had taken the bets from the class on the outcome of the deminstrations.

 

[farmer boy]

When they first began the testing they had a bunch
of bad information. They were reading volts instead
of mA, and were way off on what was required to kill
a person. When they redid the the tests, everything
but the iron killed the dummy. All too easy to kill
a human in the tub.

 

[RodinNS]

Years ago we had one of those travelling lube sales scammers here.... trying to sell one of his di-electric protective coatings. The trick was to take a drill and spray it's internals with the magic product, turn it on, then drop it in a bucket of water. The 'magic' product protected the drill. In reality, much like your example... nothing happened anyway. The drill just kept running in the bucket... and the customer was then sold on the magic solution.

Rod

 

[john *.?-!.* cub owner]

One thing that most people are misinformed on is the statement that electricity always takes the path of least resistance. It primarily takes the path of lesser resistance, but some current will flow in paths offering more resistance. The amount flows will depend on the resistance of each path.

 

[jokester]

(quoted from post at 17:48:25 08/07/13) One thing that most people are misinformed on is the statement that electricity always takes the path of least resistance. It primarily takes the path of lesser resistance, but some current will flow in paths offering more resistance. The amount flows will depend on the resistance of each path.

NOUGH!!! ENOUGH OF THIS IDLE SPECULATION! Just throw your dog/cat/wife or neighbor in a tub with a hair dryer & get the empirical results!! :twisted: