Wave Speed Calculator

What is Wave Speed?

Wave speed is the rate at which a wave disturbance propagates, measured as distance traveled per unit time. The wave speed depends on the type of wave and the medium it travels through. Mechanical waves (such as sound, water waves, and seismic waves) require a material medium and cannot propagate in a vacuum. Electromagnetic waves can propagate in a vacuum at the speed of light (about 3.00 × 108 m/s) and typically travel more slowly in materials.

Wave Speed Formula

The following formula is used to calculate the speed (magnitude of velocity) of a wave. Wave speed is calculated by multiplying the frequency of the wave in hertz by the wavelength of the wave in meters.

v = f \cdot \lambda

• Where v is the wave speed (m/s)
• f is the frequency (Hz)
• λ (lambda) is the wavelength (m)

To calculate the wave speed, multiply the frequency by the wavelength.

How is wavelength calculated?

A wavelength can be calculated using the frequency and velocity of the wave. Re-arranging the formula above, the wavelength is calculated by dividing the wave speed by the frequency.

How is frequency calculated?

Re-arranging the equation above in a different manner, you can see that the frequency is calculated by dividing the wave speed by the wavelength. Both the wavelength and frequency can be explored under the related calculators listed below.

Wave Speed Definition

Wave speed (sometimes called wave velocity) is a term used in physics to describe how fast a wave propagates through a medium or through space. This concept applies to mechanical waves (like sound and water waves) as well as electromagnetic waves (like light).

Wave Speed Example

How to calculate wave speed?

Example #1:

First, determine the frequency of the wave. For this example, the wave frequency is measured to be 50 Hz.

Next, determine the wavelength of the same wave. In this problem, the wavelength is found to be 3 meters.

Finally, we can calculate the wave speed using the formula above. v = f × λ = 50 × 3 = 150 m/s.

Example #2

As done previously, first the frequency of the wave needs to be found. Using a spectrum analyzer, the frequency is determined to be 160 Hz.

Next, the wavelength is measured to be 120 meters.

Finally, using the formula, we find the wave speed to be 160 × 120 = 19,200 m/s.

Wave Speed Units

The standard SI units for wave speed are meters per second, denoted m/s.

The English system commonly uses feet per second, denoted ft/s, as the units for wave speed.

In both of these cases, the units can be modified to other units such as inches per second and centimeters per second with a simple conversion.