AQA GCSE HIGHER PHYSICS - Calculating Wave Speed, Frequency, and Wavelength

Calculating Wave Speed, Frequency, and Wavelength

The relationship between wave speed, frequency, and wavelength is described by the following equation:

wave speed = frequency × wavelength

Where:

Wave speed is the speed at which the wave travels (measured in meters per second, m/s).
Frequency is the number of waves that pass a point in one second (measured in Hertz, Hz).
Wavelength is the distance between two corresponding points on adjacent waves (measured in meters, m).

To calculate any of the three variables, you can rearrange the equation:

Example 1: Calculating Wave Speed

A wave has a frequency of 50 Hz and a wavelength of 2 meters. What is its wave speed?

wave speed = frequency × wavelength
wave speed = 50 Hz × 2 m
wave speed = 100 m/s

Example 2: Calculating Frequency

A wave travels at a speed of 340 m/s and has a wavelength of 1.7 meters. What is its frequency?

frequency = wave speed / wavelength
frequency = 340 m/s / 1.7 m
frequency = 200 Hz

Example 3: Calculating Wavelength

A wave has a frequency of 1000 Hz and a wave speed of 340 m/s. What is its wavelength?

wavelength = wave speed / frequency
wavelength = 340 m/s / 1000 Hz
wavelength = 0.34 m

Make sure you use consistent units for all variables.
The equation can be rearranged to calculate any of the three variables.
Practice using the equation with different examples.
Remember that this equation applies to all types of waves, including sound waves, light waves, and water waves.