MCQ
The wavelength associated with an electron accelerated through a potential difference of $100\ V$ is nearly
- A$100 \mathring A$
- B$123 \mathring A$
- ✓$1.23 \mathring A$
- D$0.123 \mathring A$
✓
Answer
Correct option: C.
$1.23 \mathring A$
$ \lambda=\frac{h}{\sqrt{2 m Q V}}=\frac{6.6 \times 10^{-34}}{\sqrt{2 \times 9.1 \times 10^{-31} \times 1.6 \times 10^{-19} \times 100}}$
$=1.23 \mathring A$
$=1.23 \mathring A$
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