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SI Realization of Small Forces Using an Electrostatic Force Balance



Jon R. Pratt, John A. Kramar


We describe the realization of micronewton forces in a fashion consistent with the International System of Units (SI) using the National Institute of Standards and Technology (NIST) electrostatic force balance. A comparison between deadweight and electrostatic force is presented at a force level of approximately 200 uN. Our results demonstrate agreement between these two independent measurements at a level consistent with the uncertainties in 20 mg mass artifacts. We provide a brief description of our balance and its measurement principles, and then outline the procedures and the data analysis used to derive our results. As part of the paper, we also present a table that summarizes the uncertainties associated with realizing a 200 uN force via an electrode suspended in a measured electrostatic field. We compare this with the uncertainties associated with realizing the same force via a mass artifact in a measured gravitational field.
Proceedings Title
Proceedings of IMEKO XVIII World Congress
Conference Dates
September 17-22, 2006
Conference Location
Rio de Janeiro, BR
Conference Title
IMEKO XVIII World Congress


atomic force microscope, electrostatic force balance, instrumented indentation


Pratt, J. and Kramar, J. (2006), SI Realization of Small Forces Using an Electrostatic Force Balance, Proceedings of IMEKO XVIII World Congress, Rio de Janeiro, BR (Accessed April 12, 2024)
Created January 1, 2006, Updated February 19, 2017