Pick out the devices from the following options which convert the sound energy in to the electrical energy.
Capacitor microphones
Carbon microphones
Ribbon microphones
Microphones work on the principle of electromagnetic induction. A microphone is a device that converts sound waves into an electrical signal. Microphones are used in many applications such as telephones, tape recorders, hearing aids and in radio and television broadcasting.
Types of Microphones:-
1) Capacitor microphones- the diaphragm acts as one plate of a capacitor, and vibrations produce changes in a voltage maintained across the capacitor plates.
2) Carbon microphones- formerly used in telephone handsets. It contains carbon granules pressed between two metal plates. A voltage is applied across the metal plates, causing a current to flow through the carbon.
3) Ribbon microphones- a thin metal ribbon is suspended in a magnetic field. The vibration of the ribbon in the magnetic field generates a changing voltage.
4) Crystal and Ceramic microphones- uses the phenomenon of piezoelectricity to convert vibrations into an electrical signal. (Piezoelectricity- the tendency of some materials to produce a voltage when subjected to pressure).