Question

The diagram shows information from a sound wave. Which measurement can give the loudness of the sound?


A


B


C


D

Answer 1

Answer:

Volume

Volume (also called loudness) relates to the maximum pressure produced as particles are squeezed together as they are made to vibrate. This is also related to the maximum distance particles are moved from their normal position as they vibrate, much like how tall the ripples are in the pool mentioned before. When you show sound waves on a graph, the amplitude is the height of the waves from their middle position and reflects how loud the waves are.

Loudness of sound is measured in decibels (dB). This is actually a measure of intensity, which relates to how much energy the pressure wave has. Decibels are a relative measurement. They relate the intensity of a pressure wave to a normal or standard pressure.

For the human ear in air, the quietest noises we hear are around 10dB whereas sounds of 130dB are considered painful.