Question

If $X_L>X_C$ and $R_1=R_2$ then. Choose the correct alternative

• A. source voltage v will lead the current
• B. Power factor of box 1 will be greater than power factor of box 2
• C. Power factor of box 1 is less than power factor of circuit
• D. Voltage across box-1 will lag current

Answer 1

Answer: (A), (B), (D)

The correct options are
A

source voltage v will lead the current

B

Power factor of box 1 will be greater than power factor of box 2

D

Voltage across box-1 will lag current

Since $X_L>X_C$, the net impedance will be greater than Resistance and hence Voltage will lead current.
Power Factor of box 1 = $\frac{R}{\sqrt{R^2+(\frac{1}{\omega C}{)}^2}}$ and for Box 2 $=\frac{R}{\sqrt{R^2+(\omega L{)}^2}}$ and for the circuit it is $\frac{R}{\sqrt{R^2+(\omega L-\frac{1}{\omega C}{)}^2}}.$
In an R-C AC circuit, Voltage lags current.