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A Free-Fall Determination of the Newtonian Constant of Gravity



J P. Schwarz, D S. Robertson, T M. Niebauer, J E. Faller


We report on a recent determination of the Newtonian constant of gravity, G, using a new free fall method. This method uses a freely falling test object to sense the gravitational field of a ring-shaped mass placed alternately above and below the drop region. The measurement of the resulting acceleration signal allows us to determine G. Because makes this method valuable in the context of today's uncertainty in the value of G. We have examined the raw data in a variety of ways. We describe our methods, which allow us to extract, besides G, information about various experimental parameters and possible systematic errors. We have examined several sources of systematic errors, including magnetic and vibratiory signals arising from the dropping action of our apparatus. We outline the steps we have taken to ascertain the magnitude of errors introduced by these effects. Using the free-fall method, we have completed a determination of G, giving a result of G = (6.6873 0.0076) + 10-11 m3/Kg-sec2.
Measurement Science & Technology


gravimeter, gravity, Newton's constant, standards


Schwarz, J. , Robertson, D. , Niebauer, T. and Faller, J. (1998), A Free-Fall Determination of the Newtonian Constant of Gravity, Measurement Science & Technology (Accessed July 16, 2024)


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Created November 30, 1998, Updated October 12, 2021