Question

A series LR circuit draws a power of 550W from a 220V– 50Hz source. The power factor of the circuit in 0.8. The current in the circuit lags behind the voltage. Show that a capacitor, of value about \((\frac{1}{42\pi}\times 10^{-2})F,\) will have to be connected in the circuit to bring its power factor to unity.

Answer 1

We are given that cosϕ = 0.8

The power factor would become unity if a capacitor, C, is connected in the circuit, for which