Q 12-12-008NEETNEET 2023Top questionEasy
The radius of inner most orbit of hydrogen atom is $5.3 \times 10^{-11}$ m. What is the radius of third allowed orbit of hydrogen atom?
Answer: (D) $4.77$ Å
$r_n = n^2r_1$:
$$r_3 = 9 \times 0.53\ \text{Å} = 4.77\ \text{Å}$$
Solution by Sreeraj P, M.Sc Physics