Sound intensity refers to the amount of sound energy passing through a unit area per unit time. It measures how powerful a sound wave is at a given location and is expressed in watts per square meter (W/m²).
Key Features:
- It represents the power (in watts) that the wave delivers perpendicular to the direction of propagation.
- Higher intensity means louder sound, while lower intensity corresponds to quieter sound.
- Sound intensity decreases with distance from the source due to spreading and energy loss.
Factors Affecting Sound Intensity:
- Amplitude of the wave: Larger amplitude = greater intensity.
- Distance from the source: Intensity drops off with the square of the distance (inverse square law).
- Medium: Denser or more elastic media can affect how sound energy is transmitted.
Applications:
- Acoustic engineering for designing quiet environments or optimizing audio systems.
- Hearing protection standards depend on understanding intensity levels.
- Medical imaging (like ultrasound) uses controlled sound intensity for safety and effectiveness.