Incandescent bulb converts the electric energy into the light energy by passing the electricity through them.
It emits the light by causing the heating the filament and so become a source of electric light. These bulbs are made in an extremely wide range of sizes, watts, and voltages.
It typically consists of a glass enclosure containing a tungsten filament. An electric current passes through the filament, heating it to a temperature that produces light.
The outer glass shell of the light bulb is called the globe. The glass ensures maximum light efficiency and provides strong support for the other parts of the bulb.
The filament inside the light bulb is shaped as a coil to allow the required length of tungsten within its small environment to produce an abundant amount of light. When the bulb gets fused, its filament is broken.
Within the light bulb are inert gases usually formed of argon and/or nitrogen. These low-pressure gases prevent the filament inside the bulb from burning out; it also relieves some of the stress on the glass globe from normal atmospheric pressure, lessening the chance of glass breakage.
The base of the light bulb has three main functions. First, it securely supports the light bulb. The second job of the base is to transfer the electricity from the main electrical source to the inside of the light bulb itself. The last function is to secure the globe and all of the components inside the bulb, creating a reliable and convenient light source.
Georg Ohm first published his mathematical equation for the correct use of electricity in circuits in 1827.
A torch bulb consists of two terminals and a filament.
The filament is a spirally wound wire inside the bulb supported by two thick wires at its ends. When the positive and the negative terminals of an electric cell are connected to the two terminals of a bulb, electricity passes through the filament and it starts glowing. The terminals of the bulb are fixed in such a way that they do not touch each other.
In recent years, a different type of bulb has become popular – the compact fluorescent lamp (CFL). It is an energy-saving bulb, which has a longer life than an ordinary bulb.