Question

An electronic charge $e$ is revolving in a circular orbit of radius $r$ around a nucleus with speed $v$. The equivalent current is

• A. $\frac{ev}{2\pi r}$
• B. $\frac{2ev}{\pi r}$
• C. $\frac{ev}{4\pi r}$
• D. $\text{none of these}$

Answer 1

The correct option is A $\frac{ev}{2\pi r}$

We know that electric current is electronic charge flowing per second through a cross section. means $I=\frac{Q}{t}$

here , electric current $,I=\frac{\text{Charge}}{\text{Time period of revolution}}=\frac{e}{\left(\frac{2\pi r}{v}\right)}=\frac{ev}{2\pi r}$

Hence correct option is A.