Characteristics of Sound: Amplitude, Frequency, Time Period

TN-08-Science

Sound is produced by to and fro motion of objects. This motion is known as vibration or oscillation.

Let's take an example of sound producing turning fork which is made of steel. The two upper ends of the tuning fork are called the ‘prongs’, while the lower end is called the ‘stem’.

When we strike the prong, vibrations are produced and so does the sound.

You must have heard different type of sound. Some are very high pitch and some are very dull. Some are very loud and some are very low. All these properties of sound are controlled by different characteristics of vibration.

Let's learn about them in detail.

First characteristics of vibration is frequency. It is equal to number of oscillations completed by vibrating object in a second. It is measured in Hertz.
When frequency is high, high pitched sound is produced and when frequency is low, low pitched sound is produced.

Next characteristics is amplitude. Amplitude defined the loudness of sound. If amplitude is high, it means sound is loud. and if it is low that means sound is low in intensity.
It is measured by measuring maximum displacement of vibrating body from it's mean position. It is measured in metre.
As we move away and away from sound source, amplitude of vibration reduces and thus sound becomes inaudible.

Another characteristics is Time period which is nothing but time taken in completing one oscillation. It is related to frequency and calculated by taking inverse of it.