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Q.
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
The electric field between two charged parallel plates placed in air is E=σε0=Qε0A ...(i)
When the parallel plates are immersed in kerosene oil tank of dielectric constant K, the electric field between the plates is E′=σKε0=QKε0A=EK (Using (i)) ∴E′E=1K
As K>1, so E′<E