^Phase difference between I & V
When ac flows through a
(a) pure R, E & I are in phase i.e. Φ = 00
(b) pure L, I lags E by 900 i.e. Φ = + 900
(d) C, I leads E by 900 i.e Φ = – 900
The value of f for other cases depends upon the nature of circuit elements and their combinations.