Speed of sound across the Palikir campus

The weather decided whether this lab would be inside or outside. The morning dawned sunny with blue skies. Outside it was.


Class opened with a look at the vernal equinox sun shadow at 08:23. The noon lecture prevents a morning look at the shadow.


McGievens was assigned board clapping duty

Demonstrating the clapping technique

Darla and Jaysleen 

Leona and Jemira

Alisha


I noted that measuring wheel appeared to not always flip a digit on a click. And the third digit appeared to be getting stuck halfway between two digits. I didn't think much of the issue.


The first stop at 246 meters was too close to get accurate times. The "flash-to-bang" time was too short.


Heading west on a sunny day.


Clear day conditions 


Timing at the gym driveway 


Then, out around 925, the clicker fell off. Restoring the clicker did not flip digits. I realized that the distance data was undoubtedly erroneous. 

I tried to think of which app might record distance in meters via GPS, and discovered GPSTest doesn't.


I realized, however, that this was the perfect opportunity to use the laboratory seven conversion factor from arcminutes to meters.




The long way back to the clapper 

GPSTest data.


Leona and Stacy


Timing at road's end: Stacy, Jaysleen, Darla. Only a few made it this far due to the heat and distance.


Photocopying the data. Literally. Photographic images of the data sheet. A replacement measuring wheel, this time a metric one, has been ordered. 


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