For a series RLC circuit of resistance 1 KΩ, inductance 10 mH and capacitance 100 μF, calculate the resonant frequency for the supply voltage of 100 V.

Question

Question

This question was previously asked in

MPPKVVCL Jabalpur JE Electrical 16 August 2018 Official Paper

Answer 1

The correct answer is option 4):(159.15 Hz)

Concept:

For a series RLC circuit, the net impedance is given by:

Z = R + j (XL - XC)

XL = Inductive Reactance given by:

XL = ωL

XC = Capacitive Reactance given by:

XL = 1/ωC

The magnitude of the impedance is given by:

The current flowing across the series RLC circuit will be:

At resonance, XL = XC, resulting in the net impedance to be minimum.

This eventually results in the flow of the maximum current of:

∴ I =

Where

fo = resonant frequency in Hz

L = Inductance

C = Capacitance

Calculation:

Given: R = 1kΩ ,

L = 10mH,

C = 100 μf

Source voltage = 100 V

=159.15 Hz