WBJEE · Physics · Atomic Physics
Supose in a hypothetical world the angular momentum is quantized to be even integral multiples of \(\frac{\mathrm{h}}{2 \pi}\). The largest possible wavelength emitted by hydrogen atoms in visible range in a world according to Bohr's model will be, (Consider hc \(=1242 \mathrm{Mev}-\mathrm{fm}\) )
- A \(153 \mathrm{~nm}\)
- B \(409 \mathrm{~nm}\)
- C \(121 \mathrm{~nm}\)
- D \(487 \mathrm{~nm}\)
Answer & Solution
Correct Answer
(D) \(487 \mathrm{~nm}\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{\lambda}=R\left[\frac{1}{(2)^2}-\frac{1}{(4)^2}\right]\) \(\frac{1}{\lambda}=\mathrm{R}\left[\frac{3}{16}\right], \quad \lambda=\frac{912 \times 16}{3}=4864 \mathrm{~A}^0\) \(\lambda \approx 487 \mathrm{~nm}\)
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