A sound wave with a frequency of 1,000 cycles, traveling at 1,130 feet per second would be:
Another example is a 400 cycle sound at the same velocity (represented in figure 3).
It can be noted here, as can be seen by the two problems discussed, as the frequency increases, the wavelength decreases
and as the frequency decreases the wavelength increases, providing the medium remains the same. Audible sounds from
20 to 20,000 cps have wavelengths ranging from 55 feet to 2/3 of an inch using air as a medium. Electromagnetic waves
of the same frequencies would range in length from about 9,300 miles to approximately 9.3 miles. The reason the
electromagnetic wavelengths are so great is because the velocity is so great. Lightwaves have the same velocity as
electromagnetic waves but the frequency is so extremely high that the resulting wavelength is less than 1/1,000,000 of an
inch.
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