Understanding Sound Measurement
Sound is a vibration that propagates as an acoustic wave through a transmission medium such as a gas, liquid, or solid. In human physiology and psychology, sound is the reception of such waves and their perception by the brain.
Introduction & History
The scientific study of sound, known as acoustics, dates back to ancient Greece with Pythagoras's work on the mathematics of musical intervals. The modern understanding of sound waves developed in the 17th-19th centuries with scientists like Galileo, Newton, and Helmholtz.
Key Units
Decibel (dB)
A logarithmic unit used to measure sound intensity level, comparing a measured value to a reference level.
Hertz (Hz)
The unit of frequency, equal to one cycle per second, used to measure the pitch of sound.
Pascal (Pa)
The SI unit of pressure, used to measure sound pressure level.
Practical Applications
Audio engineering
Noise control
Music production
Hearing research
Ultrasound technology
Key Formula
Sound Intensity Level
The sound intensity level (L) in decibels is calculated as 10 times the base-10 logarithm of the ratio of the sound intensity (I) to a reference intensity (I₀, typically 10⁻¹² W/m²).