MCQ
The Bohr model of atoms
- ✓Assumes that the angular momentum of electrons is quantized
- BUses Einstein’s photo-electric equation
- CPredicts continuous emission spectra for atoms
- DPredicts the same emission spectra for all types of atoms
✓
Answer
Correct option: A.
Assumes that the angular momentum of electrons is quantized
a
(a) According to Bohr's hypothesis, electron can revolve only in those orbits in which its angular momentum is an integral multiple of $\frac{h}{2 \pi},$ where $h$ bemg the Planck's constant.
(a) According to Bohr's hypothesis, electron can revolve only in those orbits in which its angular momentum is an integral multiple of $\frac{h}{2 \pi},$ where $h$ bemg the Planck's constant.
In these orbits, angular momentum of electron can have magnitude as
$\frac{h}{2 \pi^{\prime}} \frac{2 h}{2 \pi^{\prime}} \frac{3 h}{2 \pi} \cdots \cdots \cdot$ etc $,$ but never as $\frac{1.5 h}{2 \pi^{\prime}}, \frac{2.5 h}{2 \pi^{\prime}}, \frac{3.5 h}{2 \pi} . \ldots . . .$ etc.
This is called the quantisation of angular momentum.
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