A variable–frequency supply of (rms) is available in a laboratory

PHYSICS · Subjective · CBSE · Physics · Alternating Current · Alternating Current

Problem

A variable–frequency supply of

100\,\text{V}

(rms) is available in a laboratory. A device to be tested must not draw more than

0.50\,\text{A}

(rms). A series RLC circuit is to be connected between the supply and the device so that the circuit resonates at

10\,\text{kHz}

while satisfying the current limit. A standard capacitor of

C = 2.2\,\text{nF}

(E12 series) is provided. (a) Determine the value of inductance required for the circuit to resonate at

10\,\text{kHz}

with the given capacitor. (b) Calculate the minimum resistance that must be present in series so that the rms current at resonance does not exceed

0.50\,\text{A}

when connected to the

100\,\text{V}

(rms) source. (c) If the nearest available resistor in the laboratory is

220\,\Omega

, find the rms current at resonance with this resistor and determine the percentage by which it differs from the specified current limit.