A 47Ω resistor is in series with an inductive reactance of 120Ω across an ac source. The impedance, expressed in polar form, is 129 angle 31.4° 120 angle 68.6° 129 angle 68.6° 47 angle 68.6° TRUE ANSWER : ? YOUR ANSWER : ?
When the resistor voltage in a series RL circuit becomes less than the inductor voltage, the phase angle decreases cannot be determined is not affected increases TRUE ANSWER : ? YOUR ANSWER : ?
A 12 kΩ resistor is in series with a 90 mH coil across an 8 kHz ac source. Current flow in the circuit, expressed in polar form, is I = 0.3 angle 0° mA. The source voltage, expressed in polar form, is 0.3 angle 20.6° V 3.84 angle 20.6° V 12.8 angle 20.6° V 13.84 angle 69.4° V TRUE ANSWER : ? YOUR ANSWER : ?
In a parallel RL circuit, there are 3 A rms in the resistive branch and 3 A rms in the inductive branch. The total rms current is 42.4 A 6 A 424 mA 4.24 A TRUE ANSWER : ? YOUR ANSWER : ?
A 3.3 kΩ resistor and a 120 mH coil are in parallel. Both components are across a 2 kHz, 12 V ac source. The total current in the circuit is 8.74 mA 8.74 A 874 A 874 mA TRUE ANSWER : ? YOUR ANSWER : ?
In a series RL circuit, 12 V rms is measured across the resistor, and 14 V rms is measured across the inductor. The peak value of the source voltage is 2 V 20 V 26.0 V 18.4 V TRUE ANSWER : ? YOUR ANSWER : ?
A 1.5 kΩ resistor and a coil with a 2.2 kΩ inductive reactance are in series across an 18 V ac source. The power factor is 564 6.76 55.7 0.564 TRUE ANSWER : ? YOUR ANSWER : ?
A 1.2 kΩ resistor is in series with a 15 mH coil across a 10 kHz ac source. The magnitude of the total impedance is 1526Ω 152.6Ω 942Ω 1200Ω TRUE ANSWER : ? YOUR ANSWER : ?
The voltages in Problem 5 are measured at a certain frequency. To make the resistor voltage less than the inductor voltage, the frequency is increased doubled not a factor decreased TRUE ANSWER : ? YOUR ANSWER : ?
To increase the current in a series RL circuit, the frequency should be decreased should be constant should be increased cannot be determined without values TRUE ANSWER : ? YOUR ANSWER : ?