Q165 / 180 · KCET 2020 · Physics
The period of revolution of an electron revolving in nth orbit of H-atom is proportional to
- A$n^{2}$
- B$\frac{1}{n}$
- Correct answerC$n^{3}$
- Dindependent of $n$
Solution
The time period of revolution of an electron revolving in $n$th orbit of $\mathrm{H}$-atom is given by
$\begin{array}{ll}
& T_{n}=\frac{2 \pi r_{n}}{v_{n}}=\left(\frac{4 \varepsilon_{0}^{2} h^{2}}{m e^{4}}\right) \frac{n^{3}}{z^{2}} \\
\Rightarrow \quad & T_{n} \propto n^{3}
\end{array}$
Hence, the correct answer is option: 'C'.