MCQ
An electron of mass $m$ and charge $e$ is accelerated from rest through a potential difference $V$ in vacuum. Its final velocity will be
- ✓$\sqrt{\frac{2 e V}{m}}$
- B$\sqrt{\frac{e V}{m}}$
- C$\frac{ eV }{2 m }$
- D$\frac{e V}{m}$
✓
Answer
Correct option: A.
$\sqrt{\frac{2 e V}{m}}$
a
$\frac{1}{2} m v^{2}=e V$
$\frac{1}{2} m v^{2}=e V$
final velocity of electron $(v)=\sqrt{\frac{2 e V}{m}}$.
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