Question

very urgent

A series LCR circuit is in resonance with supply voltage V=V_(0)sin(omega t) at omega=omega_(0) . Now if angular frequency (omega) of the source is being changed then mark the correct option/s regarding change in power factor.​

Answer 1

Answer:

Resonant frequency: For resonance φ=0, so XC−XL=0

$$\dfrac{1}{\omega C} = \omega L

\implies \omega^{2} = \dfrac{1}{LC}$$

∴Resonant frequencyωr=LC1

Phase difference (φ) in series LCR circuit is given by

tanφ=VRVC−VL=imRim(XC−XL)=R(XC−XL)

When current and voltage are in phase,

φ=0⟹XC−XL=0⟹XC=XL

This condition is called resonance and the circuit is called resonant circuit.