What Is the Formula for Velocity of a Wave?

The wave velocity equation is a vital tool in many areas of science and mathematics. The formula arises in fields from geology to astronomy to medicine. The basic formula for wave velocity reads as follows: "wavelength x frequency = wave velocity" where wavelength is in meters, frequency is in hertz (a unit of frequency) and wave velocity is in meters per second.

Significance

Whether we realize it or not, there are waves all around us. When we turn on a light, light waves are being emitted from the light bulb. When we turn on the radio sound waves are being emitted. When there is an earthquake, the ground shakes as a result of seismic waves.

The formula for the velocity of a wave tells scientists how fast a wave is moving, which in turn allows them to make predictions and conclusions about how various types of waves work and can be manipulated. For example, Einstein never would have been able to come up with his special theory of relativity if it wasn't for the existence of the wave velocity formula.

Function

The formula for wave velocity is "wavelength x frequency = velocity." The equation can, of course, be manipulated to calculate wavelength or frequency using simple algebra. For example, if you know the wave velocity and wavelength, you can calculate the frequency with "frequency = velocity / wavelength."

Features

The wavelength is the distance between wave crests. Wavelength is represented by the Greek letter Lambda (¬) in the wave velocity equation. The unit that represents wavelength is meters.

The frequency of a wave is how many times a wave peaks per second. The letter "f" in the wave velocity equation represents frequency. Frequency is measured in the hertz (Hz) unit.

Considerations

Sometimes it is necessary to do some preliminary calculations to determine wavelength and hertz, but once you have those values, determining wave velocity is just a matter of plugging the numbers into the wave velocity equation and doing some simple multiplication.

Effects

To see how the formula for wave velocity works, refer to this example:

Let's say the wavelength of a sound wave is 1.42m and the frequency is 260.71Hz. In order to calculate the velocity of the sound wave we put these values into their respective places in the wave velocity formula:

1.42m x 260.7Hz = wave velocity

The answer is 370.21 m/s. This is the velocity of the sound wave.

Resources

• Read this Article in Spanish
• Wave Velocity Calculator
• Wave Velocity Animation