question_answer

Two parallel metal plates having charges +Q and -Q face each other at a certain distance between them. If the plates are now dipped in kerosene oil tank, the electric field between the plates will

A)  become zero   

B)  increase

C)  decrease                           

D)  remain same

Correct Answer: B

Solution :

    The electric field in vacuum \[{{E}_{0}}=\frac{\sigma }{2{{\varepsilon }_{0}}}\] When the plates are dipped in kerosene oil tank, then the electric field between the plate will be            \[E=\frac{\sigma }{2{{\varepsilon }_{0}}k}\] \[\because \]     \[k>1\] \[\therefore \]  \[E<{{E}_{0}}\] So, the electric field between the plates will decrease.