Question

Explain briefly, using a paper diagram, the difference in the behaviour of a conductor and a dielectric in the presence of an external electric field.

Answer 1

In this question we will learn about the electric field and dielectric and study the concept behind these terms. This question put light on these interesting topics. We will study all the related information which will further lead to our solution.

Complete step by step answer:
Electric field: An electric charge is surrounded by an electric field and applies a force on different charges present in the field. Which can be of attraction or repulsion. Electric fields are the invasion of electric charges and by time-changing magnetic fields.
Here we can put light on Gauss’s law to understand the electric field of a charged sphere which tells us that the electric field environment on the outskirts of the sphere is the same as that of a point charge.
Dielectric: In dielectric under the effect of an external field, a net dipole moment induced in dielectric. Due to molecular dipole moments, a net charge appears to the surface of dielectric. These induced charges will produce a field opposing electric fields. Induced field is lesser in magnitude than the external field.
Conductor: Materials in which a charge moiety can make movement without restrictions. Inside conductor electrostatic field is zero. In conductors, surface charge density always varies with position.

In the above diagram there is a crystal-clear change in behaviour of conductor and dielectric present in an electric field. As we mentioned above what dielectrics are, so when dielectrics are projected in an electric field than as due to insufficiency of free charge carriers there a dipole moment will induce. And we know that electric fields which are induced in dielectrics are always less than that of external electric fields, so the cancellation of electric fields will not be proper. Therefore, some electric field will be persisting inside a dielectric. But if we put conductors in an external electric field the electric field inside will be zero.

Note:
In this topic we learned that induced electric fields are always less than external electric fields so there will be non-zero electric fields in a dielectric. We also learned what conductors and dielectric are. Silver is the best conductor of electric charge.