question_answer

Directions: (36-40)

Dielectric Slab

A dielectric slab is a substance which does not allow the flow of charges through it but permits them, to exert electrostatic forces on one another.

When a dielectric slab is placed between the plates, the field \[{{E}_{0}}\]polarises the dielectric. This induces charge \[-{{Q}_{p}}\] on the upper surface and \[+{{Q}_{p}}\]on the lower surface of the dielectric. These induced charges set up a field \[{{E}_{p}}\] inside the dielectric in the opposite direction of \[{{\overrightarrow{E}}_{0}}\] as shown.

In a parallel plate capacitor, the capacitance increases from \[4\,\mu F\] to \[80\,\mu F\], on introducing a dielectric medium between the plates. What is the dielectric constant of the medium?

A) 10

B) 20

C) 50

D) 100