Electrical Engineering · Question Bank

1P AC Circuits

136 of 161 questions match · page 3 of 7. Answer in your head first, then check the solution.

Study the lessons
TypeAll 136Problem solving 52Objective 84
DifficultyAll 161Easy 136Medium 22Hard 3
✕ Clear filters
#41📜 EE Pre-Board March 2016📘 PowerhouseEasy
For an RL circuit, the power factor cannot be less than ______ or greater than _____.
A0,1
B1,0
C0, -1
D-1, 0
#42📜 EE Pre-Board March 2016📘 PowerhouseEasy
In a given circuit, when the power factor is unity, the reactive power is
AMaximum
Bequal to \(I^2R\)
Czero
Dminimum
#43📜 EE Pre-Board March 2016📘 PowerhouseEasy
In a series RL circuit, the inductor current ________ the resistor current.
ALags
BLeads
Cis equal to
Dis greater than
#44📜 EE Pre-Board March 2016📘 PowerhouseEasy
A 15 ohm resistor connected in series with an inductor has an equivalent impedance of 30 ohms with an unknown angle. Find the power factor angle in degrees.
A30
B60
C45
D75
#45📜 EE Pre-Board March 2016📘 PowerhouseEasy
Transform the current given by 6 + j8 A to its time domain.
A\(100\cos(\omega t + 53.13^\circ)\)
B\(10\cos(\omega t + 53.13^\circ)\)
C\(100\cos(\omega t + 36.87^\circ)\)
D\(10\cos(\omega t + 36.87^\circ)\)
#46📜 EE Pre-Board March 2016📘 PowerhouseEasy
What is the equivalent phasor of \(i(t) = 20\cos(\omega t + 40^\circ)\) A?
A15.3 − j12.9 A
B−15.3 + j12.9 A
C15.3 + j12.9 A
D−15.3 − j12.9 A
#47📜 EE Pre-Board March 2016📘 PowerhouseEasy
A parallel RL circuit draws a total current of 17A and 1.8KW from a 120V supply. Find R.
A7 ohms
B8 ohms
C9 ohms
D10 ohms
#48📜 EE Pre-Board March 2016📘 PowerhouseEasy
A 6 ohm resistor is connected in series with an inductor L across a 110 V, 60 Hz source and draws a current of 10 A. Find L.
A25.5 mH
B26.5 mH
C23.5 mH
D24.5 mH
#49📜 EE Pre-Board March 2016📘 PowerhouseEasy
What capacitance must be placed in series with an inductance of 0.05 henry, so that when the frequency is 100 Hz, the impedance becomes equal to the ohmic resistance?
A50.7 μF
B31.8 μF
C67.5 μF
D42 μF
#50📜 EE Pre-Board March 2016📘 PowerhouseEasy
If the waveform of a current has form factor 1.2 and peak factor 1.7, find the average value of the current if the maximum value of the current is 100 A.
A45 A
B47 A
C49 A
D51 A
#51📜 EE Pre-Board March 2016📘 PowerhouseEasy
In a parallel RC circuit, as the capacitance decreases, the power factor ___________.
AIncreases
Bdecreases
CRemains the same
DBecomes zero
#52📜 EE Pre-Board March 2017📘 PowerhouseEasy
Find the reactive factor of the load having 30 kW and 50 kVA.
A0.6
B0.5
C0.8
D0.7
#53📜 EE Pre-Board March 2017📘 PowerhouseEasy
When the sole purpose of an alternating current is to produce heat, the selection of conductor is based on _______ value of the current.
Aaverage
Binstantaneous
Croot mean square
Dpeak
#54📜 EE Pre-Board March 2017📘 PowerhouseEasy
The phase angle for a series RC circuit may be computed as the angle between the __________ and __________ phasors.
Aresistance, impedance
Bresistance, reactance
Cresistance, capacitance
Dimpedance, reactance
#55📜 EE Pre-Board March 2017📘 PowerhouseEasy
The impedance triangle is similar to the __________ triangle with the resistance phasor in place of the __________.
ACurrent, resistor current
BCurrent, resistor voltage
Cvoltage, impedance
Dvoltage, resistor voltage
#56📜 EE Pre-Board March 2017📘 PowerhouseEasy
What is the frequency where the reactances of 57 μH inductor and a 57 μF capacitor are equal?
A7.92 kHz
B9.72 kHz
C2.79 kHz
D2.97 kHz
#57📜 EE Pre-Board March 2017📘 PowerhouseEasy
A resistance of 30 Ω and a capacitance of 132.6 μF are connected in series across a 220 V, variable frequency ac supply. At what frequency in Hz will the current be 4.4 A?
A30 Hz
B40 Hz
C50 Hz
D60 Hz
#58📜 EE Pre-Board March 2017📘 PowerhouseEasy
An inductive coil consumes 500 W of power at 10 A and 110 v and 60 Hz. Determine the inductance of the coil.
A24 mH
B25 mH
C26 mH
D27 mH
#59📜 EE Pre-Board March 2017📘 PowerhouseEasy
A parallel RLC circuit has R = 0.5 Ω, L = 10 mH and C = 2.5 mF. Determine the resonance frequency.
A63.66 Hz
B79.79 Hz
C112.82 Hz
D31.83 Hz
#60📜 EE Pre-Board August 2017📘 PowerhouseEasy
At what frequency will a 100 μF capacitor offer a reactance of 100 Ω?
A159 Hz
B15.9 Hz
C1.59 Hz
D31.8 Hz

More Electrical Engineering topics