How is filament connected to terminals of the bulb?
The structure of the Bulb consists of two thick contact wires in the center with a thin wire attached between them. This thin wire is called a filament. One of the thick wires is connected to the metal case at the base of the bulb and the other is connected to the metal tip at the center of the base. These two form the terminals. When electricity is passed through the terminals of the bulb, the filament gets heated up and produces light.
Image on structure of bulb
Video on structure of bulb
Some of the learners also asked: Is it possible to light a bulb when pencil moves from one terminal to another?