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AP/Calculus-Based Physics: Wave Energy Units

Examples of all types of waves are found in nature. Our understanding of the physical world is not complete until we understand the properties and behaviors of waves. Mechanical waves require a material "medium" through which to travel, electromagnetic waves do not.

  Teaching About Waves and Wave Energy (15)

  Types of Mechanical Waves (9)

  Wave Properties: Frequency, Amplitude, Period, Phase (9)

  How Waves Move and Interact: Reflection, Refraction, Interference (12)

  Standing Waves and Resonance (5)

Activities:

This simulation shows the standing wave patterns that are produced on a violin, a string medium that is fixed on both ends.  Students can toggle from 1st-5th harmonics to see the standing wave pattern of each. The sum of all the harmonics can also be displayed.

Item Type: Interactive Simulation
Level: Grades 9-12

This model simulates the wave-generating machine created by John Shive at Bell Laboratories and made famous by the Similarities in Wave Behavior film. The simulation produces sinusoidal waves by twisting the first rod with a given frequency and amplitude.  Students can set the end to be free or fixed, select a function for twisting the first rod, add a damping force, or change the length of the bars to visualize how a wave propagates in a non-uniform medium. Graphs are displayed that plot mechanical energy as a function of frequency. Advanced students can compute the speed of the traveling waves at various frequencies and plot dispersion curves.

Item Type: Computer Model
Level: High School Physics
Duration: 45 minutes

References and Collections:

The phenomenon of resonance becomes very important in structural engineering, as can be observed in this historic video of the 1940 collapse of the Tacoma Narrows Bridge.  The famous suspension bridge disaster occurred when high wind gusts set up a resonant vibration in the bridge, causing large-amplitude oscillatory motion.  This video was digitally reformatted from the original film footage shot on the scene.

Item Type: Historic Video
Level: K-12
Duration: 5 Minutes

The science of music offers a great springboard to spark student interest in wave interference, standing wave patterns, and harmonics.  This unique collection takes students on an exploration of the physics behind woodwinds, brass instruments, string, and more.  Don't miss the "Sounds of World English" section: students can map their own speaking accents.

Item Type: Digital Collection
Level: High School

Student Tutorials:

Standing waves are non-traveling vibrations.  They are produced when an incident wave and the reflected wave interfere in a way that they appear to be standing still.  Standing wave patterns are readily observable, notably in musical instruments.  This interactive tutorial gives students a good foundation for understanding why and when this complex phenomenon occurs.

Item Type: Interactive Tutorial
Level: High School Physics
Duration: One Class Period

  The Physics of Sound (6)

  Modeling Wave Behavior (1)