Sound is a longitudinal pressure wave — compressions and rarefactions in air (or any medium).
Drag the sliders
y = A · sin(k · x)
Wave lab — drag the sliders, watch it move
wave speed v = f λ = 0.60 × 110 = 66 px/s
Wave speed
In air, v ≈ 343 m/s at room temperature. So higher frequency f means shorter wavelength λ — and a higher pitch.
Your turn
A tuning fork sounds at 256 Hz. What is the wavelength of its sound in air (v ≈ 343 m/s)?
Sound is *longitudinal* — air molecules jiggle back-and-forth along the travel direction, making compressions and rarefactions. The sine curve here is a handy stand-in for the pressure.
Properties
- Frequency — pitch.
- Amplitude — loudness.
- Speed in air — about 343 m/s at room temperature.