Question

If in the process of rubbing the lenses, 6.2*1010 electrons were transferred, what is the charge of the lenses and the nylon cloth? what is the change in their masses?

Answer 1

Gives

Number of electron

$N=6.2\times10^{10}$

Charge of lenses

$q_1=ne$

$$q_1=1.6\times10^{-19}\times6.2\times10^{10}C=1\times10^{-8}C$$

$$q_2=-eN=-1.6\times10^{-19}\times6.2\times10^{10}=-1.00\times10^{-8}C$$

1electron(m)=$9.1\times10^{-31}kg$

Mass change

$$∆m=Nm=6.2\times10^{10}\times9.1\times10^{-31}kg=5.7148\times^{-20}kg$$