The electron in the hydrogen atom makes a transition from the `n = 2` energy level (or state) to the ground state (corresponding to `n = 1`). Find the frequency of the emitted photon.
Strategy: Use Eq. directly to obtain `bar(v)`, with `n_(f) = 1` (ground state) and `n_(i) = 2`. Then find the frequncy.

Explanation

To find the frequency of the emitted photon when an electron in a hydrogen atom transitions from the n = 2 energy level to the ground state (n = 1), we can use the Rydberg formula. Here’s a step-by-step solution:

### Step 1: Understand the Transition
The electron transitions from the n = 2 energy level (initial state) to the n = 1 energy level (final state). This transition emits a photon, and we need to calculate the frequency of that photon.

### Step 2: Use the Rydberg Formula
The Rydberg formula for the wavelength (λ) of the emitted photon is given by:

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