WBJEE · Physics · Atomic Physics
If the electron in a hydrogen atom jumps from an orbit with level \(\mathrm{n}_1=2\) to an orbit with level \(\mathrm{n}_2=1\) the emitted radiation has a wavelength given by
- A \(\lambda=5 / 3 \mathrm{R}\)
- B \(\lambda=4 / 3 \mathrm{R}\)
- C \(\lambda=\mathrm{R} / 4\)
- D \(\lambda=3 \mathrm{R} / 4\)
Answer & Solution
Correct Answer
(B) \(\lambda=4 / 3 \mathrm{R}\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{\lambda}=R\left(\frac{1}{n_1^2}-\frac{1}{n_2^2}\right)=R\left(\frac{1}{1^2}-\frac{1}{2^2}\right)=\frac{3 R}{4}\) \(\Rightarrow \lambda=\frac{4}{3 R}\)
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