Question

Compression and ___________ are alternately formed in a longitudinal wave.

Answer 1

1. Sound waves are longitudinal waves.
2. In longitudinal waves, particles vibrate to and fro about their mean position forming compression and rarefaction regions in the medium.
3. Compression is the region where the density of medium particles is high.
4. Rarefaction is the region where the density of medium particles is low.

Hence, compression and rarefaction are alternately formed in a longitudinal wave.