A light bulb is an electrical device that produces light.
Light bulbs produce light by passing current via a small wire known as the filament. This same filament is often constructed of tungsten, a substance that generates light when exposed to electricity.
Explanation:
A bulb contains two terminals, one to deliver electricity to the filament while the other will receive it.
Every electric equipment has two terminals, one for sending current to the device and the other for receiving it. There can be no gadget with only one terminal.
The two terminals have an important role in the completion of the circuit. It is the most important condition for working of the circuit, i.e., it must be complete and should not have any breakpoint. Due to the concept of two terminals the circuit is always complete.
The bulbs have two terminals because, a circuit can be completed only when there are both the positive terminal as well as the negative terminal, as the current flow is allowed only when the circuit is complete. Hence, the bulb has two terminals.
