A hydrogen atom initially in the ground state absorbs a photon which excites it to then n = 4 level . Estimate the frequeny of the photon.

Explanation

To solve the problem of estimating the frequency of the photon absorbed by a hydrogen atom that excites it from the ground state (n=1) to the n=4 level, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Energy Levels**:
The energy of the nth level of a hydrogen atom is given by the formula:
\[
E_n = -\frac{13.6 \, \text{eV}}{n^2}
...