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STD 12 - 12. atoms — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 12 - 12. atoms4 Marks
MCQ
In a hydrogen like atom electron make transition from an energy level with quantum number $n$ to another with quantum number $(n- 1)$. If $n > >  1$, the frequency ofradiation emitted is proportional to
  • ✓
    $\frac{1}{{{n^3}}}$
  • B
    $\;\frac{1}{n}$
  • C
    $\;\frac{1}{{{n^2}}}$
  • D
    $\;\frac{1}{{{n^{\frac{3}{2}}}}}$
✓

Answer

Correct option: A.
$\frac{1}{{{n^3}}}$
a
$\frac{v}{x}=\frac{1}{\lambda}=R Z^{2}\left[\frac{1}{n_{1}^{2}}-\frac{1}{n_{2}^{2}}\right]$

$[\because n>>1]$

$v=R C Z^{2}\left[\frac{1}{(n-1)^{2}}-\frac{1}{n^{2}}\right]$

$\operatorname{RCZ}^{2}\left[\frac{2 n-1}{n^{2}(n-1)^{2}}\right]$

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