Question

A polythene piece rubbed with wool is found to have negative charge of `3 xx 10^-7 C`. Estimate the number of electrons transferred.
A. `1.8xx10^(15)`
B. `1.8xx10^(12)`
C. `1.2xx10^(11)`
D. `1.2xx10^(10)`

Answer 1

Correct Answer - B
Here, total charge transferrred, `q=-3xx10^(-7)C`
Charge on an electron, `e=-1.6xx10^(-19)C`
From quantisation of charge, q = ne
Therefore, number of electrons transferred,
`n=(q)/(e)=(-3xx10^(7))/(-1.6xx10^(-19))`
Number of electrons, `n=1.8xx10^(12)`