An electrical method for determining the moment of inertia of a direct-current armature

The method of determination described in this paper requires for its application a direct-current quantity meter in addition to the voltmeter and ammeter used in the method described by Prof. G. Kapp.¿ It obviates, however, the necessity for drawing tangents to the curves of increasing and decreasing back-e.m.f. and can be used to give accurate results with small machines. The theory and application of this ¿quantity meter¿ method are investigated here, and experimental results are cited to show the degree of accuracy that can be obtained.