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Rubbing a comb on hair makes the comb ge...

Rubbing a comb on hair makes the comb get `-0.4C`.
(a) Find which material has lost electron and which one gained it.
(b) Find how many electrons are transferred in this process.

Text Solution

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(a) The material is comb which gained electrons and the hair gained it.
(b) Charge on 1 electron, `e= 1.6xx10^(-19)C`
`q= "ne or "n=q"/"e`
`n= 0.4"/"1.6xx10^(-19)=0.25xx10^(19)`
`=2.5xx10^(18)`.
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