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I was letting my mind freewheel, and it occurred to me that hair, containing keratin, is a polymer. It is also capable of acquiring and maintaining a charge as happens, on occasion, when brushed.

So ...

  1. Can hair be used as a dielectric in a capacitor?
  2. Do any capacitors/manufacturers use hair as an dielectric already ?
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Well, it's kind of a wacky question, but just speaking for myself I think it's okay... there's some physics involved in determining what it takes for something to be an electrolyte. The second part of your question is more marginal though, so I'm not sure if you'll get an answer to that here. – David Z Oct 8 '11 at 17:40
I'll take it (+: If hair provides a decent RoI as an electrolyte, it's probably used someplace already ... or atleast is research-underway – Everyone Oct 8 '11 at 17:50
You minds frewheeling was, ahem, very free. The fact that hair often aquires a charge by brushing is related to the fact that that hair was a rather good insulator then! So, Your introduction and the questions following are anticorrelated. – Georg Oct 8 '11 at 17:59
@Georg - My apologies. I should have used the word dielectric instead of electrolyte; I'll correct it now – Everyone Oct 8 '11 at 18:17
Both questions : NO! One of the many objectives would be: hair is slightly hygroscopic (Google for hair hygrometer). There are hundreds of technical polymeres, about a hand full of them are used in capacitors, guess why! – Georg Oct 8 '11 at 18:54

2 Answers 2

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Anything that is an insulator works as a dielectric--- you might as well substitute "insulator" for "dielectric", as they are essentially synonyms. The object doesn't need to get charged easily by static friction--- that's an incidental surface property. The dielectric properties are determined by the polarizability of the atoms in the molecules, how much the electron distribution changes relative to the nuclei when you apply an electric field.

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The exact answer to this "question" would be: "Yes, You can! But why?" – Georg Oct 10 '11 at 13:19
I answered this- it's polarization, which you can't get rid of because nuclei are always heavy and electrons are light (Born Oppenheimer) – Ron Maimon Oct 10 '11 at 18:43

Exactly you can use any insulator as dielectric.
you can use the your finger or nails or any body part as an dielectric.
because those are insulators and my classmate did the same in their lab xam when there is an shortage of capacitors in lab.

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