CUET · PHYSICS · PYQ PAPER 2025
An electron in the ground state of a hydrogen atom absorbs 12.09 eV energy. The angular momentum of the electron increases by
- A \( (h/2\pi )\)
- B \( 2(h/2\pi) \)
- C \( 3(h/2\pi) \)
- D \( 4(h/2\pi) \)
Answer & Solution
Correct Answer
(B) \( 2(h/2\pi) \)
Step-by-step Solution
Detailed explanation
\(E_i = -13.6 \text{ eV}\) \(E_f = -13.6 + 12.09 = -1.51 \text{ eV}\) \(n_f = \sqrt{\frac{-13.6}{E_f}} = \sqrt{\frac{-13.6}{-1.51}} \approx 3\) \(\Delta L = (n_f - n_i) \frac{h}{2\pi} = (3 - 1) \frac{h}{2\pi} = 2 \frac{h}{2\pi}\)
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