Question

Which of the following is polar dielectrics?
(A). HCl
(B). $NH_{3}$
(C). $H_{2}O$
(D). All of the above

Answer 1

The polar dielectric material are those materials that get aligned in the direction of the electric field when an external electric field is applied. The net dipole moment of the polar dielectric materials is due to the dipole moments of the individual molecules.

Complete step-by-step answer :
The dielectric materials are the materials having very low conductivity of heat and electricity. The dielectric materials do not show the presence of free electrons in the insulator. Even in an electric field, the current does not flow in the insulator. But the charges shift from their original position. This shifting of the charges is called dielectric polarization. The dielectric material is classified in two types:
Polar material: When the electric field is applied to the dielectric material, the material gets aligned in the direction of the electric field. The orientation of the molecules remains the same. They only rotate around the axis. These materials are known as the polar materials. The net dipole moment is the summation of the dipole moment of the individual molecules. The example of the polar dielectric materials are water, hydrochloric acid and ammonia.
Non polar dielectric: The dielectric materials having no dipole moment are known as the non-polar dielectric materials. In non-polar molecules the dipole is equal for all molecules. When the electric field is applied the positive and negative ions experience equal and opposite forces. So, the electric field produces movement of charges from their position.

Option D is correct.

Note :The electric field produced the shift of the ions in the dielectrics. The movement of the charges is the flow of the current. But slightly moving from the equilibrium position does not produce the flow of current. The flow of current is possible only when the electron flows from the positive terminal of the battery to negative terminal.