ELECTROMOTIVE FORCE AND CURRENT. 33 



The voltage E r is in phase with the current, while the 

 relative phase of the resultant voltage of the circuit is repre- 

 sented by the line O E. 



Hence the angle E r E is the angle of phase difference 

 between current and voltage in the circuit. This angle is 

 usually denoted by the symbol <P, and will be frequently 

 referred to hereafter. 



