What is a choke coil ?

Explanation

### Step-by-Step Solution:

1. **Definition of Choke Coil**: A choke coil is essentially an inductor. It is a component used in electrical circuits to limit the amount of current flowing through the circuit.

2. **Functionality**: The primary function of a choke coil is to create a voltage drop in an AC circuit. This is important for voltage regulation, as it helps ensure that appliances receive the correct voltage.

3. **Voltage Regulation**: When an appliance requires a specific voltage, and the supply voltage is higher, a choke coil can be used to drop the excess voltage. This is done by introducing the inductor into the circuit.

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