100 



KENNELLY AND VELANDER— POTENTIOMETER 



of — 97°. 2 with respect to the reference axis OR, which coincides 

 with the phase of the current I p in the potentiometer circuit. 



^ 



- ^•^'* "^^^ Osoc^/^ '^'^ a/ 



Fig. 2. Current locus, under constant impressed e.m.f. of 500 — ', of a 

 simple circuit containing inductance, resistance, and capacitance, the latter 

 being varied from 0.03 m/. to ^. 



As the capacitance in the condenser C was reduced, the vector 

 voltages at the terminals pp' advanced along the locus APBDO, 

 which is seen to be a circle passing through the origin of coordi- 

 nates R and /X. 



It is easy to demonstrate that a circular locus must apply to the 

 current and therefore to the potential difference at pp' . The im- 



