Question

________ microphones works on piezoelectric effect.

(a) Crystal

(b) Carbon

(c) Moving coil

(d) Condenser

This question was posed to me in examination.

I'm obligated to ask this question of Problems of AM topic in section Amplitude Modulation of Analog Communications

Answer 1

The correct answer is (a) Crystal

The explanation: Piezoelectric effect is the ability of materials to generate an electric charge in response to applied mechanical stress. Crystals which demonstrate the piezoelectric effect produce voltages when they are deformed. The crystal microphone uses a thin strip of piezoelectric material attached to a diaphragm. The two sides of the crystal acquire opposite charges when the crystal is deflected by the diaphragm.