Q.1
Which of the following power factors results in less energy loss in an RL circuit?
Q.2
A 470 Ω resistor and a 200 mH coil are in parallel. Both components are across a 1.5 kHz ac source. The total admittance of the circuit, in polar form, is
Q.3
To increase the current in a series RL circuit, the frequency
Q.4
When the frequency is decreased, the impedance of a parallel RL circuit Increases
Q.5
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
Q.6
A power factor of 1 indicates a purely reactive circuit, and a power factor of 0 indicates a purely resistive circuit.
Q.7
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
Q.8
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
Q.9
The resistor voltage in an RL circuit is always out of phase with the current.
Q.10
When the frequency of the voltage applied to a series RL circuit is increased, the phase angle
Q.11
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
Q.12
In an RL circuit, part of the power is resistive and part is reactive.
Q.13
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
Q.14
A 470 Ω resistor and a coil with 125 Ω inductive reactance are in parallel. Both components are across a 15 V ac voltage source. Current through the inductor is
Q.15
When the frequency of the voltage applied to a series RL circuit is decreased, the impedance
Q.16
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 ∠0° mA. The source voltage, expressed in polar form, is
Q.17
A 47 Ω resistor is in series with an inductive reactance of 120 Ω across an ac source. The impedance, expressed in polar form, is
Q.18
The impedance of an RL circuit varies inversely with frequency.
Q.19
Total current in an RL circuit always lags the source voltage.
Q.20
When the resistor voltage in a series RL circuit becomes less than the inductor voltage, the phase angle
0 h : 0 m : 1 s