From: dmacdonald_at_richfordk12.net
Date: Mon Mar 24 2008 - 14:35:04 PDT
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 59' 49" N Longitude: 72 40' 19" W Distance to Equator: 5075 km Measured shadow angle in degrees: 45.662 degrees Calculated Earth circumference: 40011 km Comments: 17 students took 18 measurements of a meter sticks shadow on March 18, 2008 throughout a time period of 40 minutes before solar noon, up to solar noon on that day (it was the only sunny day forecast for the next several days so we could not do it on the actual equinox). We took the mean of those shadow measurements and calculated our latitude using inverse tangent. We calculated the distance to the equator using a value of 111.133 km per latitude degree, and from there the circumference of the earth.