Q. The radius of electron’s second stationary orbit in Bohr’s atom is $R$. The radius of the third orbit will be
A) $3\ R$
B) $2.25\ R$
C) $9\ R$
D) $\frac{R}{3}$
Explanation
(b) $r \propto n^{2} \Rightarrow \frac{r_{(n = 2)}}{r_{(n = 3)}} = \frac{4}{9} \Rightarrow r_{(n = 3)} = \frac{9}{4}R = 2.25\ R$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.