Electrostatics Question 424
Question: An electron of mass $ m $ and charge $ e $ is accelerated from rest through a potential difference V in vacuum. The final speed of the electron will be [MP PMT 2000; AMU (Engg.) 2000]
Options:
A) $ V\sqrt{e/m} $
B) $ \sqrt{eV/m} $
C) $ \sqrt{2eV/m} $
D) $ 2eV/m $
Show Answer
Answer:
Correct Answer: C
Solution:
Kinetic energy $ K=\frac{1}{2}mv^{2}=eV $
therefore $ v=\sqrt{\frac{2eV}{m}} $
