PS3+(9-11)–10

Students demonstrate an understanding of waves by …

10a. __investigating examples of wave phenomena (e.g. ripples in water, sound waves, seismic waves)__.

10b __comparing and contrasting electromagnetic waves to mechanical waves__.

10c __qualifying the relationship between frequency and wavelength of any wave.__

What do these GSEs mean? What subtopics do students need to address to understand these GSEs?

 * waves
 * harmonic waves
 * pulses
 * examples of wave phenomena: sound, light, earthquakes, ??
 * medium
 * spectrum
 * frequency
 * waveflength
 * wave velocity
 * mechanical waves
 * electromagnetic waves
 * fields
 * dependence of wave speed on medium

What misconceptions are students likely to have about these topics?

 * [|Hapkiewicz, A. (1992). Finding a List of Science Misconceptions.] MSTA Newsletter, 38(Winter’92), pp.11-14.**
 * 1) Sounds can be produced without using any material objects.
 * 2) Hitting an object harder changes the pitch of the sound produced.
 * 3) Human voice sounds are produced by a large number of vocal cords that all produce different sounds.
 * 4) Loudness and pitch of sounds are the same things.
 * 5) You can see and hear a distinct event at the same moment.
 * 6) Sounds can travel through empty space (a vacuum).
 * 7) Sounds cannot travel through liquids and solids.
 * 8) Sounds made by vehicles (like the whistle of a train) change as the vehicles move past the listener because something (like the train engineer) purposely changes the pitch of the sound.
 * 9) In wind instruments, the instrument itself vibrates (not the internal air column).
 * 10) Music is strictly an art form; it has nothing to do with science.
 * 11) Sound waves are transverse waves (like water and light waves).
 * 12) Matter moves along with water waves as the waves move through a body of water.
 * 13) When waves interact with a solid surface, the waves are destroyed.
 * 14) In actual telephones, sounds (rather than electrical impulses) are carried through the wires.
 * 15) Ultrasounds are extremely loud sounds.
 * 16) Megaphones create sounds.
 * 17) Noise pollution is annoying, but it is essentially harmless.

What phenomena and representations help students understand these topics?
Some videos that might be useful > media type="custom" key="4061541" > > media type="youtube" key="ozn53xl-dQA" height="344" width="425" []
 * Frequency Explanation - From the University of Nottingham's [|Sixty Symbols] website.
 * Hubble Repair - A brief explanation of how JPL scientists adapted the optics on their camera to account for the distorted optics in the Hubble Telescope.
 * Ruben's Tube - For better understanding the sound wave.
 * Because sound waves in the air are always shown as Harmonic waves, such as sinusoidal signals in oscilloscope, students easily mistake sound waves as transverse waves instead of longitudinal waves. Even in this video, the sound waves are also shown as sinusoid waves, but the video gives the explanation to how the sound waves are shown as visual transverse waves.
 * The sound makes the air pressure periodic with the stretched and compressed pattern. The position with the biggest air pressure is corresponding to the position with the maximum amplitude. The wave length is shown in the following diagram.
 * Riding a huge water wave (pulse):

media type="youtube" key="kHsFhFtWm9o?rel=0" height="345" width="560" align="center"
 * What kind of science can dude (or dudette) do and still enjoy surfing? What about physical oceanography?

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What activities or activity sequences can be used to address these GSEs?

 * A Learning Sequence for Understanding Sound Waves