CBSE Class 12-science Answered

The electrons within dielectric molecules are influenced by the electric field, causing the molecules to rotate slightly from their equilibrium positions. The air gap is shown for clarity; in a real capacitor, the dielectric is in direct contact with the plates.

The induced field of the dielectric is in a direction opposite to the field between the plates of the capacitor. As the field decreases, the potential difference between the plates of the capacitor also decreases as V = Ed.

Hence capacitance increases.