Which device converts sound into electrical energy?

Which device converts sound into electrical energy?

• A. Inductor
• B. Relay
• C. Microphone
• D. Earphones and Speakers

Answer: (C)

Sound is mechanical energy in the air, and a microphone is a transducer that converts that mechanical energy into electrical energy. The diaphragm inside the microphone vibrates with the incoming sound waves, and this motion is converted into an electrical signal: in a dynamic microphone, the moving diaphragm drags a coil through a magnetic field to generate current that mirrors the waveform; in a condenser microphone, diaphragm motion changes the capacitance and produces voltage variations when biased. This is how sound becomes an electrical representation that can be amplified, recorded, or processed. Other devices don’t perform this conversion in the same direction. An inductor stores energy in a magnetic field and helps shape electrical signals, but it doesn’t turn sound into electricity. A relay uses an electrical coil to switch circuits, so it responds to electricity rather than generating it from sound. Earphones and speakers do the opposite by converting electrical energy into sound.

Sound is mechanical energy in the air, and a microphone is a transducer that converts that mechanical energy into electrical energy. The diaphragm inside the microphone vibrates with the incoming sound waves, and this motion is converted into an electrical signal: in a dynamic microphone, the moving diaphragm drags a coil through a magnetic field to generate current that mirrors the waveform; in a condenser microphone, diaphragm motion changes the capacitance and produces voltage variations when biased. This is how sound becomes an electrical representation that can be amplified, recorded, or processed.

Other devices don’t perform this conversion in the same direction. An inductor stores energy in a magnetic field and helps shape electrical signals, but it doesn’t turn sound into electricity. A relay uses an electrical coil to switch circuits, so it responds to electricity rather than generating it from sound. Earphones and speakers do the opposite by converting electrical energy into sound.