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Faraday's Cage


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this is a pretty simple concept, look it up on google if u dont know it:

 

basically my question was:

 

if u built a metal suit, wore it, and got hit by thunder, would you be fine?

 

assumin the metal can withstand the current.

 

also are there any conditions, e.g. the metal suit has to be earthed? or does it have to be perfectl smooth, or can there be lumps, bumps, for your head, or where it joins together?

 

and does a car work as faraday's cage if it is hit by ligthening, are the ppl inside fine, would they know about it? would they be electrocuted!?!

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thats the thing with faraday's cage, i believed it worked, even if u touched it.... but that just dont sound right!

 

i need a physicist like swansont, to cum along and say, yup here's the answer. coz i was sure what faraday's cage is, but it just dont sound so realistic thinking about it!

 

[read 1post / original question]

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Yes you would be fine. The current would travel through the skin of the suit because it is more conductive than your body. However it would also act as a lightning rod ensuring that you get struck.

 

I don’t think its really about the faraday cage though. Its more the skin affect.

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Yes you would be fine. The current would travel through the skin of the suit because it is more conductive than your body. However it would also act as a lightning rod ensuring that you get struck.

 

I don’t think its really about the faraday cage though. Its more the skin affect.

 

r u sure though?

(because if you touch a wire' date=' u can get an electric shock, even though the electricity can flow through the wire, onto the rest of the circuit,)

 

and in this case you would be touching the outter case, metal suit, when it gets hit by lightening, so would you get a bit of an electric shock?

 

electricity might take the path with the least resistance, but it does take all the paths! incl. the ony with higher resistance.

Proof: attach a wire to a plug, [connecting live and neutral'] 240V will go through the wire [aprox], touch that wire, and the electricity will go through u! and u will die! [prob] but the easiest path 4 the elec. is to go through the wire, but it still goes through u! as well!

Conclusion: electricity takes all paths, not only the easiest [least resistance]

 

or does it act as faraday's cage...

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Here says: "Faraday Shielding" is an entirely different effect. When a conductive object is given a DC charge imbalance' date=' the imbalance appears only on a molecule-thick skin, and the electrostatic fields only appear outside the object. Faraday shielding during a lightning strike only prevents your body from taking on an imbalanced charge. Your hair would not stand up, and there would be no corona discharges off your fingertips. But these effects aren't dangerous.[u'] Faraday shielding doesn't deal with currents, and its the current through your flesh which makes lightning dangerous.[/[/u]QUOTE]

 

so yes, its a good link, but still DOESNT answer the question:

 

if u wear a metal suit, and got hit by lightening, would u be safe, because of the faraday's cage effect, or would u be elecrtocuted, because of how electricity travels?

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If you touch a cage at a single point obviously there is no circuit meaning no shock.

If you touch it at multiple points, still there will be no shock because the potential across your body will be 0. The reason being that the faraday cage is a close metallic surface and is hece equipotential in nature.

But, the "metal suit" you intend to use as a faraday cage should be a completely closed metallic surface with no windows etc.

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But, the "metal suit" you intend to use as a faraday cage should be a completely closed metallic surface with no windows etc.

 

yeah, obviously, so if its a perfect metal suit, with no windows, or nothing like that, then am i fine?

and if its skin tight? then am i fine?

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If it is skin tight you are not fine merely because, you may not get an electric shock but you'll be roasted by the heat. When lightening will strike, there mite be transient currents developed at the skin of the metal instantaneously, which would heat up a thin suit pretty quickly. Remember that the electrical energy certainly has to dissipate some how and there is no other way for it to happen in this case other than heat.

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so yes' date=' its a good link, but still DOESNT answer the question:

 

if u wear a metal suit, and got hit by lightening, would u be safe, because of the faraday's cage effect, or would u be elecrtocuted, because of how electricity travels? [/quote']

 

Well, the key point was this:-

 

Faraday shielding doesn't deal with currents, and its the current through your flesh which makes lightning dangerous. [/size']
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yeah, so from this we assume that the metal suit would not protect from an electrical shock, so therefore, what is faraday's cage, it doesnt work, if it wont protect from an electrical shock [as lightening] it wont stop any electricity, so whats the point in it, what does it do, and what does it protect u from????????

 

im confused, all of a sudden, faraday's cage doesnt seem to work!! [but it does] ????

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Actually, I've confused myself.

 

If you were wearing a metal suit, the current would stil be conducted through your body resulting in bad things. If you were in a faraday's cage, lets assume it's a big box (or a room as the boffins call it), you would not notice anything happening.

 

The suit idea would protect you from EMP, but that isn't very useful if you still fry. If the suit was an oversized model, it could work.

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Hmmm. A faraday cage traditionally refers to a metalic mesh that will absorb electromagnetic frequencies. I'm not sure if it would save you if you were to run a current through it.

 

Heh, although incidently, there was a thread a while ago about how to avoid being tazerd. I suggested wearing a metalic mesh suit that was grounded so as to direct the current away from you... I dont not know if it would work.

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A faraday cage is a closed metal surface which does not allow any electric fields inside it. It is IMPOSSIBLE for you to get a shock sitting inside it.

 

I'm sorry, but you are not correct. A faraday cage is not some technobabble about a quasi mystical shield, it could just be a metal bucket. In fact, it is a metal bucket.

 

http://www.physics.gla.ac.uk/~kskeldon/PubSci/exhibits/E3/

 

Yup. A bucket. Stick your head in a bucket and see if lighting doesn't fry you. :P

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There is nothing mystical about it. Take a hollow conductor and you can not have an electric field inside.

Look at the first of Maxwell's equations :

[MATH]\bigtriangledown .\overrightarrow{E}=0[/MATH]

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Yes yes, great. You managed to save yourself from the electrical field. Whoo hoo. It doesn't stop the current flowing, does it?

 

The current?

 

You remember, from the lightning?

 

Kablooey?

 

The 'ohmygodithurts'?

 

Let's put it another way, in England during one thunderstorm in 1360 more knights were killed by lightning than were killed the battles of Crecy and Poitiers. The suits of armor did not protect them from the current, as they were touching the charged metal.

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