P7: MICROPHONES AND LOUDSPEAKERS

Question 1

What does a loudspeaker do?

Answer 1

use the motor effect to convert variations in current in electrical circuits to the pressure variations in sound waves

Question 2

What effect does a loudspeaker use?

Answer 2

motor effect

Question 3

How does a loudspeaker work?

Answer 3

-ac sent through coil of wire attached to a diaphragm
-the coil of wire is inside a magnetic field so a force is induced which vibrates the coil
-the diaphragm vibrates which causes air particles to vibrate, creating sound

Question 4

What does a microphone do?

Answer 4

converts vibrational energy into electromagnetic energy

Question 5

What effect does a microphone use?

Answer 5

generator effect

Question 6

How does a microphone work?

Answer 6

-sound waves cause diaphragm to vibrate which causes solenoid to move back and forth
-the solenoid is wrapped around a magnet so a current is induced as a wire is moving through a magnetic field