Question

Identify the part which vibrates to produce sound in the following instruments:
A. Dholak
B. Sitar
C. Flute

Answer 1

Hint: Disturbance in a medium results in the production of sound. Compression and rarefaction of pressure leads to the transfer of sound which vibrates to create the sound.

Complete Step-by-Step solution:
Every day we are exposed to different types of sound. Some of them were pleasant as some are very disturbing. Some are high pitched and some low pitched. The reason for the cause of all these types of sound is the same. It is nothing but vibration. Sound is produced due to the vibration of a medium, stretched membrane or a string, air column etc.
Disturbance results in the vibration of particles. Since the sound waves are longitudinal waves, the disturbed particle will exhibit to and froth motion. As a result the particle right next to the first particle will be disturbed and starts to vibrate. This will continue through the medium until its amplitude becomes zero. These vibrations result in the compression and rarefaction of pressure.

Let us discuss what happens in these three instruments separately.

a) In dholak the two ends of the instrument are covered with a thin stretched membrane. Any disturbance in the stretched membrane gives rise to a vibration. Even if it is gently beaten at the head, the stretched membrane will start to vibrate and this vibration is transferred to the surroundings. The vibrated stretched membrane results in the pressure variation inside and outside of the dholak, which results in the amplification of the sound.

b) Sitar consists mainly of two parts – a wooden hollow frame and several stretched elastic strings attached on it. When one these stretched strings is plucked, the string will start to vibrate. This vibration is suddenly transferred to the surroundings and the compression and rarefaction of pressure takes place. Along with that the air column inside the hollow frame starts to vibrate, leading to amplification of the sound. Stretched strings produce sound.

c). Flute is a small wooden hollow cylindrical instrument with some holes on it. When air is blown into it, the air column inside the hollow frame starts to vibrate. This air column will transfer the vibration to the surrounding results in the propagation of sound. So here air inside the flute produces sound.

Note: Please note that all the vibrating parts of these three instruments are elastic in nature. And always remember sound needs a medium to travel like air, water etc. The vibration of particles results in the transfer of sound.