Definition of Dielectric Loss

Dielectric loss refers to the phenomenon of absorption of electric energy by a dielectric material when it is subjected to an alternating current (AC) field.

Explanation

When a dielectric material is placed in an electric field, it becomes polarized, meaning that the positive and negative charges within the material separate, creating an electric dipole. This polarization is a result of the alignment of the electric dipoles within the material with the applied electric field.

Absorption of Electric Energy

Dielectric loss occurs when the energy of the electric field is dissipated within the dielectric material. This dissipation is mainly due to the conversion of electrical energy into heat energy. The dielectric material absorbs the energy from the electric field and converts it into thermal energy, resulting in an increase in temperature.

AC Field

Dielectric loss is predominant in AC fields because the polarity of the electric field changes with time, causing the dielectric material to continuously align and re-align its electric dipoles. This continuous movement results in the absorption and dissipation of electrical energy, leading to dielectric loss.

Comparison with Other Options

- Option B: Dissipation of electric energy by dielectric in a static field - This option is incorrect because dielectric loss occurs in an AC field, not in a static field where the polarity does not change.
- Option C: Dissipation of heat by dielectric - While this occurs as a result of dielectric loss, it does not fully encompass the concept.
- Option D: Product of loss tangent and relative permittivity - This option is incorrect because dielectric loss is not the product of these two factors, although they are related to dielectric loss.

Conclusion

Dielectric loss refers to the absorption of electric energy by a dielectric material in an AC field. It occurs due to the conversion of electrical energy into heat energy, resulting in an increase in temperature. Dielectric loss is an important factor to consider in various applications, such as capacitors and insulating materials, as it affects the efficiency and performance of the system.