This wavelength calculator works with the wave equation, the relationship that a wave's speed equals its frequency times its wavelength, and solves it for whichever quantity you need. Wavelength is the distance from one peak of a wave to the next, and together with frequency and speed it fully describes any wave, whether it is sound, light, a radio signal or a ripple on water. You choose what to solve for, the wavelength, the wave speed or the frequency, then enter the other two. To find the wavelength the calculator divides the wave speed by the frequency; to find the speed it multiplies frequency by wavelength; and to find the frequency it divides the speed by the wavelength. The wave speed depends on the medium, so use about 343 metres per second for sound in air, or about 300 million metres per second for light and other electromagnetic waves in a vacuum. A key insight from the equation is that, for a fixed speed, wavelength and frequency are inversely related, so high-frequency waves have short wavelengths and low-frequency waves have long ones, which is why bass notes and long-wave radio have such large wavelengths. This is central to the physics of sound, optics and communications. Enter your two known values to see the result straight away.
Use the wave speed in the right medium: about 343 m/s for sound, about 3 x 10^8 m/s for light. Estimate only.
The calculator uses speed equals frequency times wavelength. To find the wavelength it divides the wave speed by the frequency, to find the speed it multiplies frequency by wavelength, and to find the frequency it divides the speed by the wavelength.
A 440 hertz sound wave, the note A, travelling at 343 metres per second has a wavelength of 343 over 440, which is about 0.78 metres.
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