Experiment Report for the Eratosthenes Project on http://youth.net/
School Name: Richford Jr-Sr High School
School Location: Richford, Vermont, USA
Email Address: dmacdonald_at_richfordk12.net
Experimenter: Doug Mac Donald
Latitude 44.99462
Longitude: 72.67099
Distance to Equator: 5000.387
Measured shadow angle in degrees: 45.651
Calculated Earth circumference: 39433
Comments:
Shadow measurements were taken at 12:44 PM EDT on September 24, 2009. This was one minute off solar noon for that day, but two days after the equinox (because of overcast conditions on the 22nd and 23rd). Our Pre-Calculus class took 5 shadow measurements of a meter stick and averaged them together for a mean shadow length. We used an inverse trig function to calculate the shadow angle. Using 111.133 km per latitude degree, we calculated our distance to the equator. Then we used a proportion to calculate the circumference of the earth.
Received on Fri Sep 25 2009 - 10:04:38 PDT