Question

Name two quantities that vary periodically at a place in air as a sound wave travels through it.

Answer 1

1. A sound wave is a form of energy that flows from one point to another.
2. This flow of energy is in the form of waves.
3. Sound wave is a longitudinal wave in which particles of the medium vibrate along the direction of wave motion.
4. Flow of sound waves is in the form of compression and rarefaction.
5. Compression- It is a region of high pressure and high density in a wave motion.
6. Rarefaction- It is a region of low pressure and low density in a wave motion.
7. The sound wave represents both density change and pressure change when it moves in a medium.
8. Both pressure and the density of the medium at a given time vary with distance.
9. Thus, the two quantities that vary periodically at a place in the air as a sound wave travels through it are pressure and density.