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JEE Mains · Physics · STD 12 - 12. atoms
A \(12.5\, eV\) electron beam is used to bombard gaseous hydrogen at room temperature. It will emit
- A \(2\) lines in the Lyman series and \(1\) line in the Balmar series
- B \(3\) lines in the Lyman series
- C \(1\) line in the Lyman series and \(2\) lines in the Balmar series
- D \(3\) lines in the Balmer series
Answer & Solution
Correct Answer
(A) \(2\) lines in the Lyman series and \(1\) line in the Balmar series
Step-by-step Solution
Detailed explanation
\(\mathrm{E}=\frac{\mathrm{hc}}{\lambda} \Rightarrow \lambda=\frac{\mathrm{hc}}{\mathrm{E}}=\frac{6.62 \times 10^{-34} \times 3 \times 10^{8}}{12.5 \times 1.6 \times 10^{-19}}\) \(=993 \mathrm{A}^{\circ}\)…
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