p4

Question 1

loudspeakers

Answer 1

An alternating current flows through the wire and creates a magnetic field (electromagnetism) in the coil.

2The magnetic field of the coil interacts with the magnetic field of the permanent magnet.

3The interacting magnetic fields will exert a force on the coil (motor effect), causing it to move back or forth along the permanent magnet.

4This causes the cone to change shape.

5As the current is alternating, its magnetic field and the force it experiences will also alternate. This means that the coil of wire and cone rapidly move back and forth, meaning they vibrate.

6These vibrations are so fast that the cone vibrations cause pressure variations in the air - which are sound waves.

Question 2

loudspeakers