Electrostatics Question 687
Question: A charged ball B hangs from a silk thread S, which makes an angle $ \theta $ with a large charged conducting sheet P, . The surface charge density $ \sigma $ of the sheet is proportional to
Options:
A) $ \cot \theta $
B) $ \cos \theta $
C) $ \tan \theta $
D) $ \sin \theta $
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ T\sin \theta =\frac{\sigma }{{\varepsilon _{0}}K}.q $ ..(i)
$ T\cos \theta =mg $ .(ii)
Dividing (i) by (ii), $ \tan \theta =\frac{\sigma q}{{\varepsilon _{0}}K.mg}\text{ }\therefore \sigma \propto \tan \theta $