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Question
In a series LCR circuit, VL = VC ≠ VR. What is the value of power factor?
Solution
In an LCR series circuit, power dissipated is given by
P = I2ZcosΦ
`P/(I^2sqrt(R^2+(X_C-X_L)^2))=cosphi`
The quantity cosΦ is the power factor.
`cosphi=P/(I^2sqrt(R^2+(X_C-X_L)^2))`
∵ VL=VC and XL= XC
`:.cosphi=P/(I^2R)`
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