Introduction
The displacement current is a concept in electromagnetism that was introduced by James Clerk Maxwell to explain certain phenomena that were not accounted for by Ampere's Law. It is an important component of Maxwell's Equations, which describe the behavior of electric and magnetic fields.

Explanation
- Maxwell's Equations: Maxwell's Equations are a set of four fundamental equations that relate electric and magnetic fields to their sources. These equations are:
1. Gauss's Law for Electric Fields
2. Gauss's Law for Magnetic Fields
3. Faraday's Law of Electromagnetic Induction
4. Ampere's Law with Maxwell's Addition

- Ampere's Law: Ampere's Law relates the magnetic field around a closed loop to the electric current passing through the loop. However, Ampere's Law as originally formulated by Ampere did not take into account the changing electric fields.

- Displacement Current: The displacement current is a term introduced by Maxwell to account for the changing electric fields. It is a time-varying electric field that acts like a current and produces a magnetic field. The displacement current is given by the equation:

Id = ε₀(dE/dt)

where Id is the displacement current, ε₀ is the permittivity of free space, and dE/dt is the rate of change of the electric field with respect to time.

- Parallel Plate Capacitor: A parallel plate capacitor consists of two conducting plates separated by a dielectric material. When a potential difference is applied across the plates, an electric field is established between them, and charges accumulate on the plates. The capacitance of the capacitor depends on the area of the plates, the distance between them, and the dielectric constant of the material.

- RMS Value: The RMS (Root Mean Square) value of an AC voltage or current is the value of a steady DC voltage or current that would produce the same amount of power as the AC signal. For a sinusoidal AC signal, the RMS value is given by the peak value divided by the square root of 2.

- Calculation of Displacement Current: In this case, the capacitance of the parallel plate capacitor is given as 100pF. The RMS voltage of the AC supply is 230V, and the angular frequency is 300 rad/sec. The displacement current can be calculated using the formula:

Id = ε₀(dE/dt)

The electric field between the plates of the capacitor is given by:

E = V/d

where V is the voltage across the plates and d is the distance between the plates. Substituting the values, we get:

E = 230V/100pF = 2.3MV/m

Taking the time derivative of the electric field, we get:

dE/dt = 0

Since the voltage is constant in this case, there is no change in the electric field with respect to time, and therefore the displacement current is zero.

Conclusion
In conclusion, the displacement current in a parallel plate capacitor connected to a 230V AC supply with a frequency of 300 rad/sec is zero. This is because the voltage across the plates is