3.29 understand how an oscilloscope and microphone can be used to display a sound wave

3.29 understand how an oscilloscope and microphone can be used to display a sound wave

When sound waves enter the mircrophone, they make a crystal or a metal plate inside it vibrate. The vibrations are changed into electrical signals, and the oscilloscope uses these to make a spot which moves up and down on the screen. It moves the spot steadily sideways at the same time, producing a wave shape called waveform.

The waveform is really a graph showing how the air pressure at the microphone varies with time. It is not a picture of the sound waves themselves: Sound waves are not transverse (up and down).

Oscilloscopes are instruments used to show waveforms of electrical signals.

When we speak in microphone, sound waves are converted into electrical signals. When we connect the microphone to the oscilloscope then the oscilloscope would display waveforms onto the screen. The waveforms are a representation of sound waves.