Q 12-12-057JEE MainJEE Main 2024 (30 Jan, Shift 1)Easy
An electron of a hydrogen atom in an excited state has energy $E_n = -0.85\ \text{eV}$. The maximum number of allowed transitions to lower energy levels is ______.
Numerical value type. Enter your answer.
Answer: 6
$E_n = -\dfrac{13.6}{n^2} = -0.85 \Rightarrow n = 4$.
Maximum number of spectral lines from $n = 4$:
$$\frac{n(n-1)}{2} = \frac{4\times3}{2} = 6$$
Solution by Sreeraj P, M.Sc Physics