A 120Ω resistor is in parallel with a capacitor with a capacitive reactance of 40 Ω. Both components are across a 12 V ac source. What is the magnitude of the total impedance? 3.7Ω 4800Ω 37.9Ω 14400Ω TRUE ANSWER : ? YOUR ANSWER : ?
A positive angle of 30° is equivalent to a negative angle of –30° –60° –180° –330° TRUE ANSWER : ? YOUR ANSWER : ?
A capacitor with 150Ω of capacitive reactance is across an ac source. The impedance, expressed in polar form, is Z = 150 angle – 90° Ω Z = 150 Z = 150 angle 180° Ω Z = 150 –90° Ω TRUE ANSWER : ? YOUR ANSWER : ?
In a parallel RC circuit, there is 100 mA through the resistive branch and 100 mA through the capacitive branch. The total rms current is 282 mA 100 mA 200 mA 141 mA TRUE ANSWER : ? YOUR ANSWER : ?
A 47Ω resistor and a capacitor with a capacitive reactance of 120 are in series across an ac source. What is the circuit impedance, Z? 12.9Ω 73Ω 167Ω 129Ω TRUE ANSWER : ? YOUR ANSWER : ?
For a certain load, the true power is 150 W and the reactive power is 125 VAR. The apparent power is 275 W 195.2 W 25 W 19.52 W TRUE ANSWER : ? YOUR ANSWER : ?
A 2 kΩ resistor and a 0.002 μF capacitor are in series across an ac source. Current in the circuit is 6.50 mA. The true power is 845 mW 84.5 mW 13 mW 130 mW TRUE ANSWER : ? YOUR ANSWER : ?
In a series RC circuit, when the frequency and the resistance are halved, the impedance cannot be determined without values doubles is reduced to one-fourth is halved TRUE ANSWER : ? YOUR ANSWER : ?
A 470 resistor and a 0.2 F capacitor are in parallel across a 2.5 kHz ac source. The admittance, Y, in rectangular form, is 318.3 3.14 mS + j2.12 mS 212 2.12 mS + j3.14 mS TRUE ANSWER : ? YOUR ANSWER : ?
In a series RC circuit, 12 V(rms) is measured across the resistor and 15 V(rms) is measured across the capacitor. The rms source voltage is 3 V 27 V 19.2 V 1.9 V TRUE ANSWER : ? YOUR ANSWER : ?