MCQ
What is the angular momentum of an electron in Bohr's hydrogen atom whose energy is $-3.4 \,eV$ ?
- ✓$\frac{h}{\pi}$
- B$\frac{2 h}{\pi}$
- C$\frac{h}{2 \pi}$
- D$\frac{1}{4}$
✓
Answer
Correct option: A.
$\frac{h}{\pi}$
a
(a)
(a)
$E=-\frac{E_0}{n^2}$
$3.4=\frac{13.6 eV }{n^2}$
$n^2=\frac{13.6}{3.4}$
$n^2=\frac{68}{17}=4$
or $n=2$
Hence $m v r=\frac{n h}{2 \pi}$ or $\frac{h}{\pi}$
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