Phase Difference between E and H in Conductors

In conductors, the electric field (E) and magnetic field (H) are related to each other through Maxwell's equations. These equations describe the behavior of electromagnetic waves in a medium. The phase difference between E and H in conductors is determined by the properties of the material and the frequency of the electromagnetic wave.

Maxwell's Equations

Maxwell's equations consist of four equations that relate the electric and magnetic fields:

1. Gauss's law for electric fields: ∇ · E = ρ/ε₀
2. Gauss's law for magnetic fields: ∇ · B = 0
3. Faraday's law of electromagnetic induction: ∇ × E = -∂B/∂t
4. Ampere's law with Maxwell's addition: ∇ × H = J + ∂D/∂t

These equations describe how electric and magnetic fields are generated and how they interact with each other. In conductors, the current density (J) is non-zero, indicating the presence of free charges that can move through the material.

Phase Difference between E and H

The phase difference between E and H in conductors is determined by the relationship between the electric field, magnetic field, and current density. When an electromagnetic wave propagates through a conductor, the current density induces a magnetic field, which in turn generates an electric field. This process continues, resulting in the propagation of the wave through the conductor.

The phase difference between E and H is primarily determined by the conductivity (σ) of the material and the frequency (f) of the electromagnetic wave. It can be expressed as:

φ = arctan(σ/(ωε₀))

Where φ is the phase difference, σ is the conductivity, ω = 2πf is the angular frequency, and ε₀ is the permittivity of free space.

Explanation of the Correct Answer

The correct answer to the question is option 'C' - 45 degrees. This means that the phase difference between E and H in conductors is 45 degrees.

The phase difference of 45 degrees indicates that the electric field and magnetic field are out of phase with each other. This means that when the electric field reaches its maximum value, the magnetic field lags behind by 45 degrees. Similarly, when the magnetic field reaches its maximum value, the electric field leads by 45 degrees.

This phase difference is a characteristic property of conductors at a specific frequency. It is important to note that the phase difference can vary for different materials and frequencies. However, in general, conductors exhibit a phase difference of approximately 45 degrees between E and H.

Final Words

In summary, the phase difference between E and H in conductors is determined by the conductivity and frequency of the electromagnetic wave. Conductors typically exhibit a phase difference of 45 degrees between the electric field and magnetic field. This phase difference is a result of the interaction between the current density and the electromagnetic wave as it propagates through the conductor.