with the help of Rydberg formula find the wavelength of first line of Pfund series .

Explanation

To find the wavelength of the first line of the Pfund series using the Rydberg formula, we can follow these steps:

### Step 1: Understand the Rydberg Formula
The Rydberg formula for the wavelength of emitted light is given by:

\[ \frac{1}{\lambda} = R \left( \frac{1}{n_f^2} - \frac{1}{n_i^2} \right) \]
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