Q.

A series LCR circuit is connected to an AC source of 220 V, 50 Hz. The circuit contains a resistance R=100Ω and an inductor of inductive reactance XL=79.6Ω. The capacitance of the capacitor needed to maximize the average rate at which energy is supplied will be _________ μF.              [2023]


Ans.

(40)

To maximize the average rate at which energy is supplied, i.e. power will be maximum.

So in LCR circuit power will be maximum at the condition of resonance and in resonance condition

          XL=XC

         79.6=1ωC

  C=12π×50×79.6=40μF