From: cawhite_at_kcmsd.net
Date: Fri Sep 30 2005 - 05:32:11 PDT
Experiment Report for the Eratosthenes Project on http://youth.net/ School Name: TAPC School Location: Kansas City, Missouri Email Address: cawhite_at_kcmsd.net Experimenter: Ms. White's Environmental Science class Latitude 39 deg 6' N. Longitude: 94 deg 35' W. Distance to Equator: 4330 km Measured shadow angle in degrees: 52.8 Calculated Earth circumference: 42,120 km Comments: We used data from observations made on 9/21 because it was cloudy on 9/22. We made two shadow measurements using a meter stick to cast the shadow, taken at 1:18 CDT. The sun's altitude was calculated using the formula Tan<A=a/b where a=1 meter and b=length of the shadow in meters. Percent error=5.3% (using textbook value of 40,007 km polar circumference.)