Rarefactions

Definition

Rarefactions are regions in a longitudinal wave where the particles are spread apart, resulting in a decrease in pressure and density. They occur between compressions, which are regions of high pressure and density.

5 Must Know Facts For Your Next Test

1. In sound waves, rarefactions correspond to the troughs of the wave when represented graphically.
2. Rarefactions and compressions together form a complete cycle of a longitudinal wave.
3. The speed of sound is influenced by how quickly rarefactions and compressions travel through the medium.
4. In air, rarefactions represent areas where air molecules are less densely packed compared to compressions.
5. The wavelength of a sound wave is the distance between two consecutive rarefactions or two consecutive compressions.

Review Questions

• What happens to particle density and pressure during a rarefaction?
• How do rarefactions relate to the graphical representation of longitudinal waves?
• What role do rarefactions play in determining the speed of sound?

Related terms

Compression: Regions in a longitudinal wave where particles are close together, resulting in increased pressure and density.

Wavelength: The distance between successive crests (in transverse waves) or compressions/rarefactions (in longitudinal waves).

Longitudinal Wave: A type of wave where particle displacement is parallel to the direction of wave propagation; includes sound waves.