MCQ
The de-Broglie wavelength associated with a hydrogen molecule moving with a thermal velocity of $3 \mathrm{~km} / \mathrm{s}$ will be
- A$1 \mathring A$
- ✓$0.66 \mathring A$
- C$6.6 \mathring A$
- D$66 \mathring A$
✓
Answer
Correct option: B.
$0.66 \mathring A$
$\lambda=\frac{h}{m v_{m s}} \Rightarrow \lambda=\frac{6.6 \times 10^{-34}}{2 \times 1.67 \times 10^{-27} \times 3 \times 10^3}=0.66 \mathring A$
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