The construction and functions of electric doorbell.

Every time when we goes to frnds house or to any relatives house We always enjoy.........'tring,trong' 'tring,trong' Ya ! Definately its the sound of doorbell...electric doorbell. Do u know what is inside the doorbell that make the sound,what is its constructions. Today we will discuss about doorbell, lets starts. 1. The construction of an electric doorbell. The circuit consist of an electro-magnet, electric cell, a switch, a flexible strip of soft iron with a striker and a contant screw. The gong and striker are also present. 2. Working: When the switch is closed, a current flows in the circuit. Hence, the iron strip is attracted by the electromagnet, the metal striker strikes the metal gong and the sound is produced. Now, a gap is produced between the contact screw and the iron strip. Hence, there is no current in the circuit and the electromagnet no more attracts the iron strip. The strip being flexible returns to its normal position making contact with the screw. Therefore, the circuit is completed and sound is produced as explained earlier. The making and breaking of circuit takes place a large number of times every second and the bell continues to ring as long as the swith is closed.