Dual Nature Of Light Question 60
Question: An electron is accelerated through a potential difference of 200 volts. If $ e/m $ for the electron be $ 1.6\times 10^{11} $ coulomb/kg, the velocity acquired by the electron will be [MP PET 2000]
Options:
A) $ 8\times 10^{6},m/s $
B) $ 8\times 10^{5},m/s $
C) $ 5.9\times 10^{6},m/s $
D) $ 5.9\times 10^{5},m/s $
Show Answer
Answer:
Correct Answer: A
Solution:
$ \frac{1}{2}mv^{2}=QV\Rightarrow v=\sqrt{\frac{2QV}{m}}=\sqrt{2( \frac{e}{m} )V} $
$ \Rightarrow v=\sqrt{2\times 1.6\times 10^{11}\times 200}=8\times 10^{6}m/s $ .
BETA
