The Wave Equation
The wave equation links wave speed, frequency and wavelength, so the speed equals frequency multiplied by wavelength.
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Play with the controls to see the idea in action.
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The wave equation links wave speed, frequency and wavelength, so the speed equals frequency multiplied by wavelength.
- v equals f times lambda
- Frequency is in hertz
- Higher frequency means shorter wavelength at the same speed
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is The Wave Equation?
Within Physics, which covers forces, energy, waves, electricity, magnetism, light and space explained through motion and experiments, this topic explains The Wave Equation. Physics topics explain how things move, push, heat up and carry energy, so each one here pairs a definition with a live model you can change.
Check that you can explain The Wave Equation in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding The Wave Equation explains how the physical world behaves, from sport and transport to electricity and medicine.
The Wave Equation in detail
The wave equation links speed, frequency and wavelength: v = fλ, where v is in m/s, f in Hz and λ in metres. If frequency increases while speed stays constant, wavelength must decrease.
For a given medium, speed is fixed, so changing the frequency changes the wavelength. When a wave enters a new medium, the frequency stays the same but speed and wavelength change. For example, sound at 340 m/s with frequency 680 Hz has wavelength 0.5 m. The equation applies to all waves, including light and radio waves.
How the interactive helps you understand The Wave Equation
Watch the wave in the interactive. Use any sliders or buttons it offers to change the values and see how the wave responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of The Wave Equation.
Real-life uses and examples
- Predict what a ball, car or circuit will do with The Wave Equation before you do the calculation.
- Explain everyday devices, such as brakes, lifts or chargers, using The Wave Equation.
- Use The Wave Equation to make sense of a practical and its results.
Common mistakes to avoid
- Mixing up The Wave Equation with a related quantity that has different units.
- Forgetting that some quantities, such as force or velocity, also have a direction.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about The Wave Equation
What is The Wave Equation?
The wave equation links wave speed, frequency and wavelength, so the speed equals frequency multiplied by wavelength.
What are the most important points about The Wave Equation?
The main points are: v equals f times lambda; Frequency is in hertz; Higher frequency means shorter wavelength at the same speed.
Why is The Wave Equation useful?
Understanding The Wave Equation explains how the physical world behaves, from sport and transport to electricity and medicine.
How can I practise The Wave Equation?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to The Wave Equation?
Related topics in Physics include Refraction of Waves, Sound Waves, Light and Reflection.