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Free download in PDF Circuit Theory Short Questions and Answers for competitive exams. These short objective type questions with answers are very important for Board exams as well as competitive exams. These short solved questions or quizzes are provided by Gkseries.
41
Power factor of electric bulb is
[A]
zero
[B]
lagging
[C]
leading
[D]
unity
42
In a purely inductive circuit
[A]
actual power is zero
[B]
reactive power is zero
[C]
apparent power is zero
[D]
none of above is zero
Answer: actual power is zero
43
In any A.C. circuit always
[A]
apparent power is more than actual power
[B]
reactive power is more than apparent power
[C]
actual power is more than reactive power
[D]
reactive power is more than actual power
Answer: apparent power is more than actual power
44
Inductance of coil
[A]
is unaffected by the supply frequency
[B]
decreases with the increase in supply frequency
[C]
increases with the increase in supply frequency
[D]
becomes zero with the increase in supply frequency
Answer: increases with the increase in supply frequency
45
In a circuit containing R, L and C, power loss can take place in
[A]
C only
[B]
L only
[C]
R only
[D]
all above
46
In a pure inductive circuit
[A]
the current is in phase with the voltage
[B]
the current lags behind the voltage by 90°
[C]
the current leads the voltage by 90°
[D]
the current can lead or lag by 90°
Answer: the current lags behind the voltage by 90°
47
In a pure resistive circuit
[A]
current lags behind the voltage by 90°
[B]
current leads the voltage by 90°
[C]
current can lead or lag the voltage by 90°
[D]
current is in phase with the voltage
Answer: current is in phase with the voltage
48
In the case of an unsymmetrical alternating current the average value must always be taken over
[A]
unsymmetrical part of the wave form
[B]
the quarter cycle
[C]
the half cycle
[D]
the whole cycle
49
The power factor at resonance in R-L- C parallel circuit is
[A]
zero
[B]
0.08 lagging
[C]
0.8 leading
[D]
unity
50
The transient currents are associated with the
[A]
changes in the stored energy in the inductors and capacitors
[B]
impedance of the circuit
[C]
applied voltage to the circuit
[D]
resistance of the circuit
Answer: changes in the stored energy in the inductors and capacitors
51
The double energy transient occur in the
[A]
purely inductive circuit
[B]
R-L circuit
[C]
R-C circuit
[D]
R-L-C circuit
52
The square waveform of current has following relation between r.m.s. value and average value.
[A]
r.m.s. value is equal to average value
[B]
r.m.s. value of current is greater than average value
[C]
r.m.s. value of current is less than average value
[D]
none of the above
Answer: r.m.s. value is equal to average value
53
The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces
[A]
the more heat than produced by A.C. when flowing through the same circuit
[B]
the same heat as produced by A.C. when flowing through the same circuit
[C]
the less heat than produced by A.C. flowing through the same circuit
[D]
none of the above
Answer: the same heat as produced by A.C. when flowing through the same circuit
54
In a loss-free R-L-C circuit the transient current is
[A]
oscillating
[B]
square wave
[C]
sinusoidal
[D]
non-oscillating
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