Question

What can the propagation of sound be visualised as?
(More than one option can be correct.)

• A. Propagation of density variations
• B. Propagation of pressure variations
• C. A series of compressions and rarefactions
• D. A transverse wave

Answer 1

Answer: (A), (B), (C)

A series of compressions and rarefactions

During vibration, when a particle moves forward, it compresses the air in front of it and creates a high pressure or high density region. This region is known as compression.
When a particle moves backward, it creates a low pressure or low density region. This region is known as rarefaction.
When sound propagates in a medium, the particles of the medium vibrate along the direction of propagation of wave.
Therefore, sound wave is a longitudinal wave.