2023 · Q27
Consider the following statements about the microphone and the speaker of a mobile phone:
- 1The microphone converts sound to a mechanical signal.
- 2The microphone converts sound to an electrical signal.
- 3The speaker converts a mechanical signal to sound.
- 4The speaker converts an electrical signal to sound.
Which of the statements given above are correct?
General KnowledgePhysics
- A1 and 3
- B1 and 4
- C2 and 3
- D2 and 4
Explanation
Statement 2 is true: the microphone's diaphragm moves a coil/membrane to convert sound waves into an electrical signal. Statement 4 is true: the speaker does the reverse, converting an electrical signal into diaphragm vibrations that produce sound. Statements 1 and 3 are false because neither device outputs/inputs a 'mechanical signal' as its electrical interface. Hence statements 2 and 4 are correct.