Practice Questions

1.Does a microphone use the motor effect or generator effect?

Generator effect

2. Suggest why this type of microphone is referred to as a moving coil microphone

When the sound wave strikes the diaphragm cone, it causes the diaphragm cone to move forwards and backwards. As the coil is attached to the diaphragm cone it also moves forwards and backwards.

3. Explain how this microphone works

When the sound wave strikes the black diaphragm cone, it causes the cone to vibrate backwards and forwards. 

The cone is attached to a wire coil, so as the cone moves forwards and backwards, so does the coil. 

This will cause the coil to cut the magnetic field lines setting up an alternating induced potential difference across the ends of the coil, due to the generator effect. 

If the coil is part of a complete circuit, then an alternating current will flow.