Home » Past Questions » Physics » in a series R-L-C circuit at resonance, the voltages across the resistor and the...

in a series R-L-C circuit at resonance, the voltages across the resistor and the...


Question

in a series R-L-C circuit at resonance, the voltages across the resistor and the inductor are 30V and 40V respectively, what is the voltage across the capacitor?

Options

A) 30V

B) 40V

C) 50V

D) 70V


The correct answer is B.

Explanation:

At resonance, inductive reactant XL is equal to the capacitive reactance XC
i.e. XL = XC
and XL = VL/IL
and XC = VC/IC

Again since the components are in series, the same current flows in the series arrangment
i.e. IL = IC
at resonance, VL/IL = VC/IC
∴ VL = VC
= 40V


More Past Questions:


Dicussion (1)

  • At resonance, inductive reactant XL is equal to the capacitive reactance XC
    i.e. XL = XC
    and XL = VL/IL
    and XC = VC/IC

    Again since the components are in series, the same current flows in the series arrangment
    i.e. IL = IC
    at resonance, VL/IL = VC/IC
    ∴ VL = VC
    = 40V

    Reply
    Like