The Wave Addition Interactive is an adjustable-size file that displays nicely on smart phones, on tablets such as the iPad, on Chromebooks, and on laptops and desktops. The size of the Interactive can be scaled to fit the device that it is displayed on. The compatibility with smart phones, iPads, other tablets, and Chromebooks make it a perfect tool for use in a 1:1 classroom.


Teaching Ideas and Suggestions:

This Interactive has enough features to become the launch pad for just about any aspect of wave motion. While its intended purpose is to promote an understanding of concepts of wave addition, it could easily be used for numerous other functions. For instance, the Wave Addition Interactive addresses the following learning outcomes.

  • To explain how a wave can be an example of periodic motion. (Use the Unit CircleAmplitude Bars, or Line feature of the program.)
  • Describe the meaning of the various wave properties - amplitude, speed, wavelength, and frequency. (Make alterations in the values of these properties and observe the effect such alterations have on the wave pattern.)
  • Describe the effect (if any) that an alteration of frequency has upon the wavelength and the speed of the wave. (Change the value of the frequency and view its effect or non-effect on he wavelength and the speed values.)
  • Distinguish between longitudinal and transverse waves by comparing the direction of wave motion to the direction of the particle motion. (Tap on the Longitudinal and the Transverse button for either one of the waves.)
  • Distinguish between constructive and destructive interference and to explain how one can predict which would occur at a given location along the medium. (Tap ono the Construct and the Destruct buttons and explore. Use the Bar feature to view Amplitude Bars on the wave display.)
  • Describe the principle of superposition and demonstrate how it could be used to determine the resultant displacement of the medium at a given location that results from the interference of two waves. (Alter the amplitude of one or both waves and use the built-in Scale and Line functions in order to measure the displacement of the red wave, the blue wave, and the wave sum at any location along the medium.)
  • Describe what beats are and explain how they are formed. (Tap on the Beat 1 or Beat 2 buttons.)
  • Write and interpret the equations that describe the position, velocity, and acceleration values of various points along the medium. (Tap on the equation buttons for either one or both of the waves. There are equations for position (y), velocity (v), and acceleration (a)).
  • Describe what a standing wave is and explain how one is formed. (Tap on the Standing T or the Standing L buttons to view transverse or longitudinal standing wave patterns).

The Physics Classroom has prepared an activity titled Wave Interference for use with this Interactive. The Wave Interference activity allows users to explore the following concepts:

  • Interference occurs when two or more waves meet up while traveling through the same medium.
  • The distinction between constructive and destructive interference.
  • The displacement of the particles of the medium at any given point can be determined by adding the displacements caused by the individual waves.
  • The principle of superposition describes how to determine the displacement of the resultant at a given location.

Our Wave Addition simulation is now available with a Concept Checker. Do the simulation. Then follow it up with the Concept Checker.


Related Resources

There are numerous resources at The Physics Classroom website that serve as very complementary supports for the Wave Addition Interactive. We have included resources here that address wave addition concepts and the other concepts that can be explored through the use of this Interactive. These include: 
  • Minds On Physics Internet Modules:
    The Minds On Physics Internet Modules include a collection of interactive questioning modules that help learners assess their understanding of physics concepts and solidify those understandings by answering questions that require higher-order thinking. Assignments WM6, WM7, and WM8 of the Wave Motion module provide great complements to this Interactive. They are best used in the middle to later stages of the learning cycle. Visit the Minds On Physics Internet Modules.

  • Curriculum/Practice: Several Concept Development worksheets at the Curriculum Corner will be very useful in assisting students in cultivating their understanding, most notably ...

    Standing Wave Mathematics
    Interference of Waves

  • Labwork: 
    Simulations should always support (never supplant) hands-on learning. The Laboratory section of The Physics Classroom website includes several hands-on ideas that complement this Interactive. Three notable lab ideas include ...

    Nodes and Antinodes Lab
    Harmonic Frequency Lab
    Wave Behavior Demonstration Lab
    Who Can Hear Monte Tone Lab

    Visit The Laboratory.
  • Science Reasoning Activities:
    Science classrooms should be filled with reasoning activities. There are two related activities in the Waves section and the Sound section of the Science Reasoning Center that will challenge students to employ close reading, data analysis, and logical reasoning. The activities are named ...

    Standing Waves on a Rope
    The Sound of Music

    Visit the Science Reasoning Center.

Additional resources and ideas for incorporating Wave Addition Interactive into an instructional unit on waves and sound can be found at the Teacher Toolkits section of The Physics Classroom website.  Visit Teacher Toolkits.


We owe a special thanks to Physics teacher Martin Kirby for contributing this simulation to our Interactives collection. If you like this sim, you can tap on the Donate button and buy him a cup of coffee (or a pot of coffee); he'd appreciate it. Martin has contributed many other simulations to our Interactives collection. You can view them all by visiting our page listing all Martin Kirby Simulations. Or visit Martin's website ( to learn more.

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