Can an Insulator Acquire Same Charge as Charged Body?

AI Thread Summary
When a charged body approaches an insulator, the side facing it acquires an opposite charge due to induction, but insulators cannot retain this induced charge. In high electric fields, insulators can become positively charged through field-emission of electrons or negatively charged by collecting electrons from other sources. Charge cannot be induced on insulators through standard methods, but in high voltage scenarios, charge can be deposited within insulators. The van deGraaff generator demonstrates charge transfer, where charge is wiped onto a dielectric belt and then transferred to a metal sphere. Overall, while insulators can interact with electric fields, they do not acquire the same charge as a nearby charged body through induction.
akhil123
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When a charged body is brought near an insulator, the side facing it acquires a charge of opposite sign because of induction. Is it possible for an insulator to acquire same charge as charged body? (by induction, touching or any other means)
 
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akhil123 said:
When a charged body is brought near an insulator, the side facing it acquires a charge of opposite sign because of induction. Is it possible for an insulator to acquire same charge as charged body? (by induction, touching or any other means)

Yes. The belt on a van deGraaff generator picks up charge in this way.
 
An insulator in an electric field gets charged positively by field-emission of electrons in very high electric fields, or negatively by electrons collected from other field-emitting sources. Charge cannot be induced (Faraday induction) on insulators. In very high voltage situations, charge can get deposited in (as opposed to on) insulators.

Bob S
 
Bob S said:
An insulator in an electric field gets charged positively by field-emission of electrons in very high electric fields, or negatively by electrons collected from other field-emitting sources. Charge cannot be induced (Faraday induction) on insulators. In very high voltage situations, charge can get deposited in (as opposed to on) insulators.

Bob S

I was referring to the "other means" part of the question. In the Wikipedia description of a van deGraaff generator, it looks to me like the combs "wipe" charge onto (or into) the conducting, dielectric belt. Once conveyed to the large metal sphere at the top of the loop, the charges are wiped off of (or out of) the belt by the upper comb, and migrate to the sphere's outer surface where they can build up considerably before spontaneously draining away into the ambient air.
 
Thanks a lot
 
akhil123 said:
Thanks a lot

You're welcome. I know the "scraping" idea is a lame one, but it was how one of these contraptions was explained to me in a high school physics class.
 
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