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ERIC Number: EJ864420
Record Type: Journal
Publication Date: 2009-Nov
Pages: 3
Abstractor: As Provided
Reference Count: 5
ISSN: ISSN-0031-921X
Measuring the Radius of the Earth from a Mountain Top Overlooking the Ocean
Gangadharan, Dhevan
Physics Teacher, v47 n8 p533-535 Nov 2009
A clear view of the ocean may be used to measure the radius of the Earth. To an observer looking out at the ocean, the horizon will always form some angle [theta] with the local horizontal plane. As the observer's elevation "h" increases, so does the angle [theta]. From measurements of the elevation "h" and the angle [theta], the radius "R" of the Earth may be found. This paper describes an experiment in which measurements were taken at an elevation of approximately 485 m in the Santa Monica hills of Los Angeles, CA. The average refraction-corrected value for the radius of the (assumed spherical) Earth was found to be 6100 [plus or minus] 420 km. The accepted value at the equator is 6380 km.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Identifiers - Location: California