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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

Verified by Experts

(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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