Magnetic Effects Of Current Question 234
Question: An electron is launched with velocity $ \vec{v} $ in a uniform magnetic field $ \vec{B} $ . The angle $ \theta $ between $ \vec{v} $ and $ \vec{B} $ lies between 0 and $ \pi /2 $ . Its velocity vector $ \vec{v} $ returns to its initial value in a time interval of
Options:
A) $ \frac{2\pi m}{eB} $
B) $ \frac{2\times 2\pi m}{eB} $
C) $ \frac{\pi m}{eB} $
D) Depends upon angle between $ \vec{v} $ and $ \vec{B} $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] Time interval in which $ \vec{v} $ returns to its initial value is same as time period of the particle, hence the required time $ =\frac{2\pi m}{eB} $
BETA
