Lesson Plan

Relate the amplitude of a sound wave to its loudness and energy

Define sound intensity as power per unit area and compute it from power, area, or pressure amplitude

Describe the decibel scale and compute sound intensity level using β = 10 log₁₀(I/I₀)

Distinguish sound intensity (W/m²) from sound intensity level (dB)

Describe how humans hear sound and how the vocal cords produce sound and control pitch and loudness

14.2

"In general, the intensity of a wave is the power per unit area carried by the wave." "The sound intensity level $\beta$ is defined to be $\beta \text{ (dB)} = 10 \log_{10}\left(\frac{I}{I_0}\right)$, where I is sound intensity in watts per meter squared, and $I_0 = 10^{-12} \text{ W/m}^2$ is a reference intensity." "Sound intensity level is not the same as sound intensity—it tells you the level of the sound relative to a reference intensity rather than the actual intensity." "The perception of frequency is called pitch, and the perception of intensity is called loudness."