Why do bulbs have two terminals?

Explanation

### Step-by-Step Solution:

1. **Understanding Bulb Structure**: A bulb consists of a glass enclosure that contains a filament inside. The filament is the part that produces light when electricity passes through it.

2. **Identifying the Terminals**: At the base of the bulb, there are two metal contacts known as terminals. These terminals are crucial for the functioning of the bulb.

3. **Function of Terminals**: The primary function of the two terminals is to connect the filament to an external power source, such as a battery or a cell. Each terminal connects to one end of the filament.

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