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

Gujarat BoardEnglish MediumSTD 11 ScienceNEETSTD 12 - 12. atoms4 Marks
MCQ
A monochromatic light is incident on a hydrogen sample in ground state. Hydrogen atoms absorb a fraction of light and subsequently emit radiation of six different wavelengths. The frequency of incident light is $x \times 10^{15}\,Hz$. The value of $x$ is (Given $h =4.25 \times 10^{-15}\,eVs$ )
  • A
    $2$
  • ✓
    $3$
  • C
    $4$
  • D
    $8$
✓

Answer

Correct option: B.
$3$
b
$6={ }^4 C _2 \quad \Rightarrow n _2=4$

$h v= E _4- E _1$

$\therefore v=13.6\left(\frac{1}{1^2}-\frac{1}{4^2}\right) \times \frac{1}{4.25 \times 10^{-15}}$

$=3 \times 10^{15}\,Hz$

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