What is displacement current? Explain its cause.

Explanation

### Step-by-Step Solution:

**Step 1: Understanding Displacement Current**
Displacement current is a concept introduced by James Clerk Maxwell to explain how a changing electric field can produce a current in a region where there is no actual flow of charge carriers (like electrons). It is particularly important in the context of capacitors and time-varying electric fields.

**Step 2: The Role of a Capacitor**
Consider a capacitor connected to an alternating current (AC) source. When the AC source operates, it creates a time-varying electric field between the plates of the capacitor. During the positive half cycle of the AC voltage, one plate of the capacitor becomes positively charged while the other becomes negatively charged.

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