Though the drift velocity of electorn responsible for current in a conductorn under ordinary circumstances is very small, light in a room turn on immediately after the swithc is closed, Explain why and how?

Explanation

To explain why the light in a room turns on immediately after the switch is closed, despite the drift velocity of electrons being very small, we can break down the explanation into several steps:

### Step 1: Understanding Drift Velocity
- **Drift velocity** is the average velocity that a charge carrier, such as an electron, attains due to an electric field. In a typical conductor, this drift velocity is quite small, often on the order of millimeters per second.

### Step 2: The Role of the Electric Field
- When the switch is closed, a **potential difference** (voltage) is applied across the conductor. This creates an **electric field** within the conductor almost instantaneously.

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