Newton's gravitational constant with uncertainty less than 100 ppm

Abstract

We have obtained a value for Newton's gravitational constant (coverage factor of 1) of G=6.6656(6)/spl times/10/sup -11/ m/sup 3/ kg/sup -1//spl middot/s/sup -2/ with a combined standard uncertainty of 95 ppm. The method is based on a torsion balance which is servocontrolled to constant angular position with an electrostatically induced torque balancing the gravitationally induced torque. This electrostatically induced torque is calibrated using an acceleration method.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>