Electrostatics Question 298
Question: An electric dipole is placed along the $ x- $ axis at the origin $ O $ . A point $ P $ is at a distance of $ 20cm $ from this origin such that $ OP $ makes an angle $ \frac{\pi }{3} $ with the x-axis. If the electric field at $ P $ makes an angle $ \theta $ with the x-axis, the value of $ \theta $ would be [MP PMT 1997]
Options:
A) $ \frac{\pi }{3} $
B) $ \frac{\pi }{3}+{{\tan }^{-1}}( \frac{\sqrt{3}}{2} ) $
C) $ \frac{2\pi }{3} $
D) $ {{\tan }^{-1}}( \frac{\sqrt{3}}{2} ) $
Show Answer
Answer:
Correct Answer: B
Solution:
$ \theta =\frac{\pi }{3}+\alpha $ where $ \tan \alpha =\frac{1}{2}\tan \frac{\pi }{3} $
therefore $ \alpha ={{\tan }^{-1}}\sqrt{3}/2 $ so, $ \theta =\frac{\pi }{3}+{{\tan }^{-1}}\sqrt{3}/2 $
