Introducing Sine Waves in Trigonometry with a RipStik

In order to introduce the graph of a sine wave in MS 101 Algebra and Trigonometry, chapter 6.4 of Larson's text of the same name. This was done out on the porch.
 Starting my run towards a sheet of paper on the porch.
 The towel is wet and dyed with blue food color. Only after I did these runs did I discover that the cement was rough enough to effectively emboss the sine wave into the paper without the need for the wet towel. I would later successfully perform a "dry imprint" using the RipStik in my physical science class two days later.

 The RipStik produced a wavelength of 32 centimeters at a period of 0.4 seconds with an amplitude of 4 centimeters. WolframAlpha was used to then generate a graph of the function. My inability to determine how to control the aspect ratio results in an exaggerated vertical axis for the graph.

Larson does not introduce wavelength, focusing instead on period. Larson also leaves the calculation of the frequency for a homework problem involving a tuning fork (number 77 in the seventh edition, number 91 in the eighth edition). I introduced both of those concepts along with the product of the frequency and wavelength producing the wave speed.

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