Sound

Definition

Sound is a mechanical wave that propagates through a medium such as air, water, or solids by the vibration of particles. It is characterized by properties such as frequency, wavelength, amplitude, and speed.

5 Must Know Facts For Your Next Test

1. Sound waves are longitudinal waves where particle displacement is parallel to the direction of wave propagation.
2. The speed of sound varies depending on the medium and its temperature; it travels faster in solids than in liquids and gases.
3. The frequency of sound determines its pitch: higher frequencies correspond to higher pitches.
4. Amplitude affects the loudness of sound; greater amplitudes produce louder sounds.
5. The human ear can typically hear sounds ranging from 20 Hz to 20 kHz.

Review Questions

• What type of wave is a sound wave and how does it propagate through different media?
• How does the speed of sound vary between different states of matter (solids, liquids, gases)?
• What are the relationships between frequency, amplitude, and the perceived characteristics of sound (pitch and loudness)?

Related terms

Frequency: $\text{Frequency}$ refers to the number of oscillations or cycles per unit time in a wave. In sound, it determines pitch and is measured in Hertz (Hz).

Wavelength: $\text{Wavelength}$ is the distance between consecutive points of identical phase in a wave. For sound waves, it is inversely related to frequency.

Amplitude: $\text{Amplitude}$ measures the maximum displacement of particles from their rest position due to a wave. Higher amplitude means louder sound.