what is the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n=4 to and energy level with n=2 ?

Explanation

To find the wavelength of light emitted when an electron in a hydrogen atom transitions from an energy level of \( n=4 \) to \( n=2 \), we can follow these steps:

### Step-by-Step Solution

1. **Identify the Initial and Final Energy Levels**:
- The initial energy level (\( n_i \)) is 4.
- The final energy level (\( n_f \)) is 2.

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