972 Hz Wavelength

How Long Is a 972 Hz Wavelength?

A 972 Hz sound wave has a wavelength of 0.35 meters, 35.31 cm, 1.16 feet (1 feet and 1.9 inches) or 13.9 inches when traveling in air at 20°C (68°F).

The formula for the wavelenght is λ = c/f where:

  • c is the celerity (speed) of sound = 343.21 m/s or 1126.03 ft/s in air at 20°C (68°F).
  • f is the frequency = 972 Hz
which gives a wavelength λ of 0.35 meters, or 1.16 feet.

972 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 972 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 972 Hz wavelength (cm)972 Hz wavelength (in)
-40-4031.490012.3976
-35-3131.825812.5299
-30-2232.158212.6607
-25-1332.487212.7902
-20-432.812812.9184
-15533.135313.0454
-101433.454613.1711
-52333.771013.2957
03234.084413.4190
54134.394913.5413
105034.702713.6625
155935.007713.7826
206835.310113.9016
257735.610014.0197
308635.907314.1368
359536.202314.2529
4010436.494814.3680

972 Hz Half Wavelength and Standing Waves

The half wavelength of a 972 Hz sound wave is 0.18 meters, 17.66 cm, 0.58 feet (0 feet and 6.95 inches) or 6.95 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 972 Hz in rooms where two opposing walls (axial mode), edges (tangential mode) or corners (oblique mode) are spaced by a distance d = nλ/2 where:

  • n is a natural (positive integer greater than or equal to 1)
  • λ is the 972 Hz wavelength = 0.35 meters, or 1.16 feet in air at 20°C (68°F).

972 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.180.58
20.351.16
30.531.74
40.712.32
50.882.90

We typically don't treat rooms for standing waves above 300 Hz.

Given the relatively small 972 Hz half wavelength, you can treat your room by using thick acoustic foam. This will absorb frequencies as low as 250 Hz, and all the way up to 20,000 Hz.

How To Convert 972 Hz To ms

A Hz (Hertz) is a cycle (or period) per second.

Because a 972 Hz wave will ocillate 972 times per second, we can find the time of a single cycle (or period) with the formula p = 1/f where:

  • f is the frequency of the wave = 972 Hz

The result will be expressed in seconds, so let's multiply by 1000 to get miliseconds:

1 / 972 Hz * 1000 = 1.03 ms.