The radius of electron's second stationary orbit in Bohr's atom is R. The radius of 3rd orbit will be
Solution
$r \propto \frac{n^{2}}{Z}$
<br/><br/>$$
\begin{aligned}
& \frac{r_{2 { nd }}}{r_{3 \mathrm{rd}}}=\left(\frac{n_{2}}{n_{3}}\right)^{2} \\\\
& \Rightarrow \frac{R}{r_{3 r d}}=\left(\frac{2}{3}\right)^{2} \\\\
& \Rightarrow r_{3 \mathrm{rd}}=\frac{9}{4} R \\\\
& =2.25 R
\end{aligned}
$$
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Bohr's Model of Hydrogen Atom
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