question_answer

Direction: Q.16 to Q.20

When an insulator is placed in an external field, the dipoles become aligned. Induced surface charges on the insulator establish a polarization field \[{{\overrightarrow{E}}_{i}}\] in its interior.

The net field \[\overrightarrow{E}\]in the insulator is the vector sum of \[{{\overrightarrow{E}}_{0}}\] and \[{{\overrightarrow{E}}_{i}}\]as shown in the figure.

On the application of external electric field, the effect of aligning the electric dipoles in the insulator is called polarisation and the field \[{{\overrightarrow{E}}_{i}}\] is known as the polarization field.

The dipole moment per unit volume of the dielectric is  known as polarisation \[\left( \overrightarrow{P} \right)\].

For linear isotropic dielectrics, \[\overrightarrow{P}=\chi \overrightarrow{E}\], where \[\chi \] = electrical susceptibility of the dielectric medium.

Read the given passage carefully and give the answer of the following questions.

Which among the following is an example of polar molecule?

A) \[{{O}_{2}}\]                           

B) \[{{H}_{2}}\]

C) \[{{N}_{2}}\]                           

D) \[HCl\]