The constraints are examined which may be obtained for the parameters of long-range hypothetical interactions by the use of the precise experimental setup created originally for the calibration of accelerometers. This setup includes the large rotating steel sphere with a nonconcentric spherical cavity in which the strictly homogeneous gravitational field arises. The field of additional interaction produced by the atoms of the sphere, however, is not homogeneous. The essential features required of the detector of additional interaction which is the torsional pendulum of high sensitivity are discussed. Both the cases of the Yukawa-type and degree-type hypothetical interactions are investigated. It is shown that the known-to-date constraints for Yukawa-type interactions may be strengthened by a factor of 400 in the appropriate interaction range. For the degree-type hypothetical forces decreasing with distance as r-3, r-4 and r-5 correspondingly the known constraints may be strengthened by the factors of 90, 35 and 20. The conclusion is made that with the use of the specially created related setup it will be conceivable to strengthen the constraints for Yukawa-type interactions up to 4500 times over a wide interaction range.

To investigate the dynamic characteristics of high-sensitivity graviinertial devices (accelerometers, seismometers, and others) it seems advantageous to use for the input signal the gravitational acceleration produced by bodies with a known mass distribution. This eliminates the need for moving the transducer under investigation. Such motion is needed in the inertial acceleration reproduction as well as for inclining a measuring instrument in the Earth's gravity field. Error in measuring the parameters of the transducer motion is determined by the uncertainties of the length- and angle-measuring instruments being used. Particularly, it concerns the angle measurement errors when the gravity field effects have been taken into account. The existing methods for reproducing gravitational acceleration are based on the use of nonuniform fields of simple shape bodies (sphere, cylinder, and the like). These methods require calculation of the corresponding acceleration, taking into account the spatial mass distribution of the instrument sensing element. The commonly employed approximation results in a procedural error of the order of 10% and over. It is proposed to calibrate a measuring instrument using a uniform, flat gravity field of varying direction. The set-up designed to realize this method reproduces varying accelerations over the frequency range 0.01 to 0.3 Hz with amplitude less than 1.3 × 10−7 m/sec2. This enables calibration of seismometers of various types with a higher accuracy.