Question

A current of $1\text{A}$ is drawn by the filament of an electrical bulb. The number of electrons passing through a cross-section of the filament in $16\text{s}$ will be roughly -

• A. ${10}^{20}$
• B. ${10}^{16}$
• C. ${10}^{18}$
• D. ${10}^{23}$

Answer 1

The correct option is A ${10}^{20}$

We know that, electric current,

$I=\frac{Q}{t}$

$\Rightarrow 1=\frac{Q}{16}$

$\Rightarrow Q=16\text{C}$

Also,

$Q=ne$; $e$ is charge on one electron

$\Rightarrow 16=n\times 1.6\times {10}^{-19}$

$\Rightarrow n={10}^{20}$ electrons

Hence, option $\left(A\right)$ is the correct answer.