Waves day two

The rain and shortened period on Monday provided an opportunity to start from the RipStik wave on Wednesday.


The RipStik wave was put up on the board. The colored magnets were too weak to hold the paper up.

Gear included the rope, spring, meter stick, tape measure, and a timer. 

The golf ball was brought along but not used. The rope was used to re-introduce, wavelength, period, and frequency. 

Amplitude was unintentionally omitted due to oversight. 


The spring was then used to demonstrate both transverse versus longitudinal (compression) waves with definitions echoed onto the whiteboard. The spring provides a visual connector from a transverse rope wave to a compressional sound wave.



The sciencemusic site had a good sound simulation that ran on the Smartboard. This provided a nice bridge from the dance of the "moles-cules" of the unit on heat to the sine wave that sciencemusic can also produce in another simulation. The sound simulation displays very nicely how the sound wave compressions and rarefactions are superimposed on the motion of the molecules in the air. The simulation includes a volume and frequency control, as well as the option to send a wave train or a single wave.


The class wraps up with hearing range and hearing damage - which would really require a high end tweeter and a true frequency generator. No oscilloscope was demonstrated, the online oscilloscope did not ask for microphone permission and was thus unable to display a waveform. Not sure what the issue was as the online oscilloscope has functioned in the past. 

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