POE - Lesson 3: AC Theory Homework
What is the phase angle of a circuit with a resistance of 28Ω and a reactance of -1120.3Ω?
-88.57º
What is the power factor of a circuit with a phase angle of 88.57 degrees?
0.025
How much current will flow from a 1kHz oscillator at 1.23V RMS in a circuit with a resistance of 10k Ohms, a capacitance of 22 microfarads, and an inductance of 10 microhenries?
0.123mA
What is the capacitive reactance to 1Hz in a 1F capacitor?
0.16Ω
What is the power factor of a circuit with a phase angle of 45 degrees?
0.707
What is the Real Power of a 12A, 120VRMS motor with a power factor of 0.74?
1065.6W
What is the impedance of a 100Hz circuit with a resistance of 100Ohms, an inductance of 100mH, and a capacitance of 100 microfarads?
110.46Ω
The hot conductors for 3 Phase power have a phase angle of
120º
What is the total reactance of a circuit with an inductive reactance of 142 Ohms and a capacitive reactance of 7.04 Ohms?
134.96Ω
What is the impedance of a circuit with a resistance of 10 Ohms and a reactance of 10 Ohms?
14.14Ω
What is the inductive reactance to 40Hz in a 565mH inductor?
142Ω
What is the Apparent Power of a 12A, 120VRMS motor with a power factor of 0.74?
1440VA
What is the phase angle of a circuit with a power factor of 0.95?
18.19º
What is the Reactive Power of a 4.5A, 120VRMS motor with a power factor of 0.91?
223.85VAR
What is the impedance of a circuit with a resistance of 39 Ohms and a reactance of 23 Ohms?
45.28Ω
What is the phase angle of a circuit with a resistance of 5Ω and a reactance of 5Ω?
45º
What is the phase angle of a circuit with a power factor of 0.65?
49.46º
What is the Real Power of a 4.5A, 120VRMS motor with a power factor of 0.91?
491.4W
What is the Real Power of a 5A, 120VRMS motor with a power factor of 0.83?
498W
How much current will flow at 208V RMS , 60Hz, through a 100mH inductor?
5.52A
What is the Real Power of a 3 Phase, 17A, 208VRMS motor with a power factor of 0.86?
5260.86W
What is the Apparent Power, of a 4.5A, 120VRMS motor with a power factor of 0.91?
540VA
What is the impedance of a 60Hz circuit with a resistance of 14Ω, an inductance of 12mH, and a capacitance of 4.7 microfarads?
560.04Ω
What is the total reactance of a circuit with an inductive reactance of 6.28 Ohms and a capacitive reactance of 0.16 Ohms?
6.12Ω
What is the inductive reactance to 1Hz in a 1H inductor? __________________
6.28Ω
What is the capacitive reactance to 40Hz in a 565 microfarad capacitor?
7.04Ω
How much current will flow at 208V RMS , 60Hz, through a 100 microfarad capacitor?
7.84A
What is the Real Power of a 3 Phase, 12A, 480VRMS motor with a power factor of 0.93?
9267.26W
What is the Reactive Power of a 12A, 120VRMS motor with a power factor of 0.74?
968.58VAR
_____________________ power is simply the product of current and electromotive force in an AC circuit.
Apparent
The unit of measure for Power Factor is _______________________.
No unit
The unit of measure for impedance is _______________________.
Ohms
The unit of measure for capacitive reactance is _______________________.
Ohms (Ω)
The unit of measure for inductive reactance is _______________________.
Ohms (Ω)
The unit of measure for total reactance is _______________________.
Ohms (Ω)
_____________________ power flows in the power conductors but does not do any work; it is "wattless" power.
Reactive
_____________________ power is the power that is consumed by the load.
Real
The unit of measure for Apparent Power is _______________________.
Volt-Amps (VA)
The unit of measure for Reactive Power is _______________________.
Volt-Amps-Reactive (VAR)
The unit of measure for Real Power is _______________________.
Watts (W)
Enjoy a free points cookie:
Yum
The power factor of an inductive load may be increased with ______________.
capacitance
A circuit with a total reactance of -100 Ohms is a(n) ____________________ load.
capacitive
______________________ reactance decreases as frequency increases.
capacitive
A circuit with a total reactance of 100 Ohms is a(n) ________________________ load.
inductive
______________________ reactance increases as frequency increases.
inductive
The "ELI the ICEman" mnemonic is a common way to remember that current lags voltage in an _____________________, and voltage lags current in a _____________________.
inductor, capacitor
A power factor of 0.95 is ______________ desirable than a power factor of 0.65.
more
Impedance is the vector sum of resistance and ________________.
reactance
Power Factor (pf) is the ratio of _________________ power to _____________________________ power.
real, apparent
