Question

If the radius of $2^{nd}$ Bohr orbit of hydrogen atom is $r_2$ The radius of third Bohr orbit will be

• A. $\frac{4}{9}{r}_2$
• B. $4r_2$
• C. $\frac{9}{4}{r}_2$
• D. $9r_2$

Answer 1

Answer: (C)

$r=\frac{n^2{h}^2}{4{\pi }^{2}mZ{e}^2}$
$\therefore \frac{r_2}{r_3}=\frac{2^2}{3^2}$
$\therefore r_3=\frac{9}{4}{r}_2$