Sometimes, when we visit to a hairdresser’s shop for cutting or shaping our hair we find them often using an appliance for drying hair. Now, how does this hair drier work? We are aware of the fact that the electric heater, electric bulb, immersion heater, etc. are the domestic appliances which work on the heating effects of electric currents. Hair drier also works on the same principle.
A hair drier consists of a cover usually made of plastic. It is shaped like a pistol. Inside this plastic cover, a coil of nichrome wire is fitted. The coil gets heated up when electric current is passed through it. This heating element is made from special resistance materials. At the back of this coil, a very small electric fan is fitted. It has two switches which make the current flow through the fan and the nichrome coil. When one switch is put on, the electric fan starts running and the cold air comes out from the plastic cover. When the second switch is put on, the coil gets heated up and as a result the wind blown by the fan also gets heated. The fan blows moisture laden air away from hairs continuously, replacing with fresh dry air. The machine is widely used in some circles as an essential house-hold item.
This apparatus is not only used for drying hair but also for drying in the research laboratories in a number of experiments where drying process is necessary.
