i) State the condition undert which the phenomenon of resonance occurs in a series LCR circuit.
ii) Plot a graph showing variation of current with frequency of ac source in a series LCR circuit.
iii) At resonance what is the value of power factor in the case of LCR series circuit ?
Answers
Answered by
7
(i) In a series LCR circuit, resonance occurs when reactance of the inductor and capacitor are equal.
Condition is XL=XC
XL is inductive reactance and XC is capactive reactance.
(ii) please refer attached document for the graph required
(iii) At resonance, the net reactance is (XL-XC) = zero. So, the LCR circuit becomes entirely resistive in nature. In this case, phase angle is zero since the voltage and current of resistance are in same phase.
Power factor is cosine of phase angle. i.e. cos 0° = 1
Power factor is unity at resonance for LCR circuit
Attachments:
Similar questions