MCQ
An electron is accelerated from rest through a potential difference of $V$ volt. If the de Broglie wavelength of the electron is $1.227 \times 10^{-2}\, nm ,$ the potential difference is $......V$
- ✓$10^{4}$
- B$10$
- C$10^{2}$
- D$10^{3}$
✓
Answer
Correct option: A.
$10^{4}$
a
$\lambda=1.227 \times 10^{-2} nm$
$\lambda=1.227 \times 10^{-2} nm$
$=0.1227 \mathop A\limits^o $
$\lambda=\frac{12.27}{\sqrt{ v }} \mathop A\limits^o$
$0.1227=\frac{12.27}{\sqrt{ v }} \mathop A\limits^o$
$\sqrt{ v }=10^{2} \Rightarrow v =10^{4} volt$
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