question_answer

A sphere of radius R has a uniform distribution of electric charge in its volume. At a distance x from its centre, for , the electric field is directly proportional to [MP PMT 1994; AIIMS 1997; BCECE 2005]

A)                   

B)                                       

C)                   

D)                                     

Correct Answer: C

Solution :

 Let sphere has uniform chare density  and E is the electric field at distance x from the centre of the sphere. Applying Gauss law  ( Volume of dotted sphere) \  Þ