JEE Mains · Physics · STD 12 - 12. atoms
According to Bohr's theory, the moment of momentum of an electron revolving in \(4^{\text {th }}\) orbit of hydrogen atom is _______.
- A \(8 \frac{\mathrm{h}}{\pi}\)
- B \(\frac{\mathrm{h}}{\pi}\)
- C \(2 \frac{\mathrm{h}}{\pi}\)
- D \(\frac{\mathrm{h}}{2 \pi}\)
Answer & Solution
Correct Answer
(C) \(2 \frac{\mathrm{h}}{\pi}\)
Step-by-step Solution
Detailed explanation
Moment of momentum is \(\vec{r} \times \vec{P}\) \(\overrightarrow{\mathrm{L}}=\overrightarrow{\mathrm{r}} \times \mathrm{m} \overrightarrow{\mathrm{v}}\) \(\mathrm{L}=\mathrm{mvr}=\frac{\mathrm{nh}}{2 \pi}=\frac{4 \mathrm{~h}}{2 \pi}=\frac{2 \mathrm{~h}}{\pi}\)
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