RipStik wave

Summer 24 the pre-laying of the centerline was ill-conceived at best and failed miserably. Spring 2024 I forgot to shut down the timer at the end of the run and El Niño winds tore off one of the four sheets. Fall 2023 the timer was in the wrong mode. Summer 2023 the centerline was not held. This term I did not attempt a prelaid centerline. I also went out well ahead of class and made runs up and down the sidewalk practicing timings between walkway poles. I used four sheets again, but waited to lay out the sheets until noon when I had some assistance. Winds were light this term. I moved the paper west to help get a stable line up and running before hitting the paper. Once the class convened I did some timing runs alongside the paper, they were running at about 2 seconds. I did multiple passes before I attempted a single pass. I worked on holding a steady centerline, starting and stopping the timer. 

 

The complication with this layout was that the class did not move. The day was hot and sunny, so sitting alongside the paper was not an option - too hot.  I wound up lecturing to just the few students down on the sidewalk. The rest were pretty much out of the loop except when I stood up to walk back east and ask questions. 

The RipStik run location is good. The class location is suboptimal. The only solution seems to be to back up the inbound run further downslope to the east. Maybe the new parking lot will be an option in some future term - but not on a sunny day like today.

Fumi-Kate throws a fast shaka as I photograph the layout. 

This term I did not measure the whole paper and use that to estimate the wavelength. 

Wavelength of 72 cm. 4.25 waves on the paper in 1.94 seconds. 5 cm amplitude. Period was 0.46 seconds, frequency was 2.19 Hertz. A calculated wavespeed of 158 cm/s. 

This term went well, nothing forgotten, and the pre-class rehearsal was valuable. The centerline was certainly not straight, but not as bad as it could have been.