Displacement Current: Displacement Current is a concept in electromagnetism that was introduced by James Clerk Maxwell to modify Ampere’s law. According to Ampere’s law, the magnetic field around a wire is proportional to the electric current flowing through the wire. However, Maxwell realized that this law is incomplete because it only accounts for the magnetic field generated by the flow of electric charges, but does not account for the magnetic field generated by changing electric fields.

To address this issue, Maxwell added a new term to Ampere’s law, known as the displacement current. The displacement current is a term that represents the time-varying electric field, and it is proportional to the rate of change of the electric flux through a surface. Mathematically, it is given by:

I_d = ε₀(dΦ_E / dt)

where,

• I_d is the displacement current,
• ε₀ is the permittivity of free space, and
• dΦ_E / dt is the rate of change of the electric flux through a surface.

Equation of Displacement Current

It has the same unit and effect on the magnetic field as is for conduction current depicted by Maxwell’s equation-

Where,

• H is related to magnetic field B as B = μH
• μ is the permeability of the medium in between the plates.
• J is the conducting current density.
• J_D  is the displacement current density.

Follow on Facebook

By Team Learning Mantras