A falling- weight time switch: its standardization and application to the determination of the time constant of an inductive circuit
Eric J. Irons, G. A. Bennett · Proceedings of the Physical Society · 1939
In this apparatus the simultaneous release of two spheres, one from a fixed height and the other from a known but variable height H , causes two switches to be thrown so that the time interval between their operation is a linear function of radical H . The apparatus is tested by a condenser-discharge method which affords a determination of g with an accuracy of about ½ per cent. The use of the device is illustrated by a study of current growth in an inductive circuit for which the time constant is deduced.