Torch Bulb

Small electric bulb which produces ligh t when the torch is switched on is known as a Torch Bulb.

What are the different components of a Torch Bulb?

• It has an outer case of glass which is fixed with a metallic base .
• Inside the glass bulb are very thin wires which are fixed to two thick wires, this thin wire is known as a filament .
• Filament of the bulb glow when electricity from a cell is passed through it.
• These thick wires provide support to the filament.
• One of the metal wires is connected to a metal case and the other is connected to the metal tip at the centre of the base. They are known as two terminals of the bulb.
• The two terminals are fixed in such a way that they do not touch each other.

How does a Torch bulb give light?

1. It is the filament of the bulb which glows when electricity from a cell is passed through it.
2. The metal tip at the base of the bulb and metal case of bulb are two terminals of a torch bulb. 
3. When electricity from a cell passes through filament , the filament gets heated up too much and becomes white and starts giving light.