When electric current passes through a thin, high resistance tungsten filament of an electric bulb, the filament becomes hot and emits light. This is the heating effect of electric current.
Electric light bulbs
A light bulb is a device that uses electricity to generate light. By passing current through a thin wire known as the filament, light bulbs convert electricity into light. Tungsten is a substance that emits light as electricity is passed through it, so the filament is normally made of it.
- Electric bulb contains a thick metallic wire made up of tungsten metal.
- The metal is kept in an inert environment with a neutral gas or vacuum.
- When current flows through the tungsten wire, it becomes heated and emits light.
- Most of the electric power drawn in the circuit from the electrical source is dissipated in the form of heat and the rest is emitted in the form of light energy.