Question

A parallel plate capacitor is charged by connecting it to a battery through a resistor. If I is the current in the circuit, then in the gap between the plates, there is no conduction current:

Options

• Displacement current of magnitude equal to I flows in the same direction as I.

• Displacement current of magnitude equal to I flows in a direction opposite to that of I.

• Displacement current of magnitude greater than I flows but can be in any direction.

• None of these.

Answer 1

Displacement current of magnitude equal to I flows in a direction opposite to that of I.

Explanation:

Let us draw the structure according to the given condition. We get:

According to modified Ampere’s law:

`oint B * dl` = μ₀ (I_C + I_D)

For Loop L₁, I_C ≠ 0 and I_D = 0

For Loop L₂, I_C ≠ 0 and I_D = 0

Due to KCL,

I_C = I_D

∴ Displacement current of magnitude equal to I flows in a direction opposite to that of I.