RipStik Wave Physics Introduction

This term I tried riding my RipStik across the paper on the porch outside of the classroom without using water or dye.
 
Two sheets of poster pad were lightly taped to the cement on a rainy day. Donnalyn assists with a measurement that found the two sheets are 167 centimeters long.



I then rode my RipStik across the two sheets while timing the run.


The cement is quite rough and has red mud ground into it. The result was a nice stippled sine wave line on the paper. The 167 cm run took 1.84 seconds.



The first run was untimed, the traces of it can be seen at the top of the paper above. Below I have used marker to trace the path of one of the wheels. I covered wavelength, linear board velocity, frequency, period, and wave speed before I ran out of time. Amplitude will have to wait until Wednesday.

The dry cement imprint was far superior to the dyed water track approach.


Above one can see more clearly the slightly brown, stippled wheels tracks crimped into the paper. The two tracks are the two sets of wheels on the RipStik.

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