In an RLC series circuit the phase angle between the current and voltages is 30 $\degree$.If the AC frequency doubles,what is the resulting phase angle?
A)30 $\degree$
B)more than 30 $\degree$
C)less than 30 $\degree$
D)Additional information is needed to reach a determination.

Question

Quizplus · Accepted Answer

The phase angle in an RLC series circuit is given by arctan((XL-XC)/R), where XL and XC are the reactance of inductor and capacitor respectively. As the AC frequency doubles, the reactances of the inductor and capacitor also double. Therefore, the numerator of the phase angle equation increases, which means that the phase angle will increase. Hence, the resulting phase angle will be more than 30 degrees. Therefore, the correct answer is B.

In an RLC Series Circuit the Phase Angle Between the Current