EE SHORT NOTES-A.C. FUNDAMENTALS 1

1 Poor power factor results in all of the following EXCEPT.
Reduction
in power losses

[other wrong options are – Overloading of transformers, Overloading of altemators,
Reduction in load handling capacity of electrical system, ]
2 The dual of a loop is
Node
pair

[other wrong options are – Twig, Mesh, Tree, ]
3 Higher the Q of a series circuit
Narrower
its pass band

[other wrong options are – Broader its resonance curve, Greater its band
width, Sharper its resonace, ]
4 When an alternating current passes through an ohmic resistance the
electrical power converted into heat is
True
power

[other wrong options are – Apparent power, Reactive power, None of the
above, ]
5 For the full wave rectified sine wave the r.m.s. value is
0.707
Imax

[other wrong options are – 0.636 Imax, 0.318 Imax,
Zero, ]
6 In A.C. circuit laminated iron is invariably used in order to
Reduce
eddy current loss

[other wrong options are – Increase heat radiation, Make assembly cheap and
easier, Reduce circuit permeability, ]
7 In a circuit containing R, L and C, power loss can take place
R
only

[other wrong options are – C only, L only, All of the above, ]
8 All the rules and laws of D.C. circuit also supply to A.C. circuit
containing
Resistance
only

[other wrong options are – Capacitance only, Inductance only, All above, ]
9 How much r.m.s. current does a 300 W. 200V bulb take from the 200 V, 50
Hz power line ?
1.5
A

[other wrong options are – 0.5A, 2A, 3A, ]
10 The r.m.s. value and mean value is the same in the case of
Square
wave

[other wrong options are – Triangular wave, Sine wave, Half wave rectified
sine wave, ]
11 The period of a wave is
Time
required to complete one cycle

[other wrong options are – The same as frequency, Expressed in amperes,
None of the above, ]
12 The capacitors for power factor correction are rated in terms of
kVAR
[other wrong options are – Voltage, VA, kW, ]
13 Two sinusoidal quantities are said to be phase quadrature, when their
phase difference is
90°
[other wrong options are – 0, 30°, 45°, ]
14 A coil with large distributed capacitance has a
High
resonant frequency

[other wrong options are – Low resonant frequency, Low quality factor, Low
resistance, ]
15 A resonance curve for a series circuit is a plot of frequency versus
Current
[other wrong options are – Voltage, Impedance, Reactance, ]
16 The unit of frequency of an A.C. signal is
Hertz
[other wrong options are – Cycle, Cycle-sec, Hertz/sec, ]
17 The power taken by a 3-Φ load is given by the expression
√3 VL IL cosΦ
[other wrong options are – √3 VL IL
sinΦ, 3 VL IL sinΦ, 3 VL IL
cosΦ, ]
18 In an A.C. circuit, a low value of kVAR compared with kW indicates
High
power factor

[other wrong options are – Low efficiency, Unity power factor, Maximum Load
current, ]
19 In a pure resistive circuit
Current
is in phase with the voltage

[other wrong options are – Current lags behind the voltage by 90°, Current leads
the voltage by 90°, Current can lead or lag the voltage by 90°,
20 Inductance affects the direct current flow
At
the time of turning on and off

[other wrong options are – Only at the time of turning off, Only at the
time of turning on, At all the time of operation, ]

                              Part 1  Part 2   Part 3  Part 4  Part 5

EE SHORT NOTES-A.C. FUNDAMENTALS 2
EE AND ECE IMPORTANT MCQ-Transistors 1

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