An electron in H -atoms jumps from some higher level to 3rd energy level.If three spectral lines are possible for the transition, find the initial position of electron.

Explanation

To solve the problem of determining the initial position of an electron in a hydrogen atom that jumps to the 3rd energy level and produces three spectral lines, we can follow these steps:

### Step 1: Understand the Concept of Energy Levels
In a hydrogen atom, electrons occupy discrete energy levels, which can be represented by principal quantum numbers (n = 1, 2, 3, ...). When an electron transitions from a higher energy level to a lower one, it emits a photon, which corresponds to a spectral line.

### Step 2: Determine the Number of Spectral Lines
The number of spectral lines produced when an electron transitions from an initial energy level (n_i) to a final energy level (n_f) can be calculated using the formula:
\[ \text{Number of lines} = \frac{(n_i - n_f)(n_i - n_f + 1)}{2} \]
...