Dual Nature Of Light Question 39
Question: An electron is accelerated through a potential difference of 1000 volts. Its velocity is nearly [MP PMT 1985; Pb. PET 2003]
Options:
A) $ \frac{{\nu_{1}}-{\nu_{2}}}{k-1} $
B) $ 1.9\times 10^{6}m/s $
C) $ 1.9\times 10^{7}m/s $
D) $ 2\sqrt{2}V $
Show Answer
Answer:
Correct Answer: C
Solution:
If the voltage given is V, then the energy of electron $ \frac{1}{2}mv^{2}=eV\Rightarrow v=\sqrt{\frac{2eV}{m}} $ $ =\sqrt{\frac{2\times 1.6\times {{10}^{-19}}\times 1000}{9.1\times {{10}^{-31}}}}=1.875\times 10^{7} $ $ \approx 1.9\times 10^{7}m/s $
BETA
