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Weekly Exam 1 - DC & Ac Circuits

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CERTC Weekly Exam 1 EE Subjects

DC and AC Circuits
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Multiple Choice:
17. Find the node voltage VA.
1. You are measuring the current in a circuit that is operated on an 18 V battery. The
ammeter reads 40 mA. Later you notice the current has dropped to 20 mA. How
much has the voltage changed?
A. 9 V C. 0 V
B. 900 mV D. 18 V
2. If you wish to increase the amount of current in a resistor from 120 mA to 160 mA
by changing the 24 V source, what should the new voltage setting be?
A. 8 V C. 320 V
B. 3.2 V D. 32 V
A. 6 V C. 4.25 v
3. A 120 V lamp-dimming circuit is controlled by a rheostat and protected from B. 12 V D. 3 V
excessive current by a 3 A fuse. To what minimum resistance value can the
rheostat be set without blowing the fuse? Assume a lamp resistance of 20 ohms. 18. What is the current through R2?
A. 40 W C. 4 W
B. 2 W D. 20 W
4. Which of the following series combinations dissipates the most power when
connected across a 120 V source?
A. 0ne 220 W resistor C. three 220 W resistors
B. two 220 W resistors D. four 220 W resistors
5. All the voltage drops and the source voltage added together in a series circuit is
equal to
A. the total of the voltage drops
B. the source voltage A. 3.19 A C. 1.73 A
C. zero B. 319 mA D. 173 mA
D. the total of the source voltage and the voltage drops
19. What is the voltage drop across R1?
6. To measure the current out of the second resistor in a circuit consisting of four
resistors, an ammeter can be placed:
A. between the second and the third resistors
B. at the negative e terminal of the source
C. between the third and the fourth
D. at any point in the circuit
7. The total resistance of a circuit is 680 W. The percentage of the total voltage
appearing across a 47 W resistor that makes up part of the total series resistance
is?
A. 68% C. 69% A. 850 mV C. 9.18 V
B. 47% D. 6.91% B. 7.82 V D. 918 mV
8. The output of a certain voltage divider is 12 V with no load. When a load is 20. In assigning the direction of branch currents,
connected, the output voltage A. the directions are critical C. they must point into a node
A. decreases C. remains the same’ B. the directions are not critical D. they must point out of a node
B. increases D. becomes zero
21. The branch current method uses:
9. A certain voltage divider consists of two 12 kW resistors in series. Which of the A. KCL and KVL
following load resistors will have the most effect on the output voltage? B. Thevenin’s theorem and Ohm’s law
A. 1 MW C. 18 kW C. KCL and Ohm’s law
B. 24 kW D. 12 kW D. Superposition theorem and Thevenin’s theorem
10. Three 10 kW resistors are connected in series. A 20 kW resistor is connected in 22. One sine wave has a positive-going zero crossing at 15° and another sine wave
parallel across one of the 10 kWresistors. The voltage source is 24 V. The total has a positive-going zero crossing at 55°. The phase angle between the two
current in the circuit is waveforms is:
A. 900 µA C. 90 mA A. 0° C. 70°
B. 9 mA D. 800 µA B. 40° D. none of these
11. A certain voltage divider consists of three 1 k resistors in series. Which of the 23. A square wave has a period of 60 µs. The first odd harmonic is
following load resistors will have the least effect on the output voltage? A. 5 kHz C. 500 kHz
A. 1 MW C. 1 kW B. 50 kHz D. 33.33 kHz
B. 100 kW D. 330 W
24. A phasor represents:
12. The parallel combination of a 470 W resistor and a 1.5 kW resistor is in series A. the magnitude and a quantity direction
with the parallel combination of five 1 kWresistors. The source voltage is 50 V. B. the width of a quantity
The percentage of the load current through any single 1 kW resistor is: C. the phase angle
A. 25% C. 100% D. the magnitude of a quantity
B. 20% D. 50% 25. In a series RC circuit, 12 V(rms) is measured across the resistor and 15 V(rms) is
13. A certain Wheatstone bridge has the following resistor values: R1 = 10 kW, R2 = measured across the capacitor. The rms source voltage is
720 W, and R4 = 2.4 kW. The unknown resistance is A. 3V C. 19.2 V
B. 27 V D. 1.9 V
A. 24W C. 300W
B. 2.4W D. 3,000 W 26. An ac circuit consists of a resistor and a capacitor. To increase the phase angle
above 45°, the following condition must exist:
14. On which of the following voltage range settings will a voltmeter present the
A. R=Xc C. R<Xc
minimum load on a circuit?
B. R>Xc D. R=5Xc
A. 1 V C. 500 v
B. 50 V D. 1,000 V 27. For a certain load, the true power is 150 W and the reactive power is 125 VAR.
The apparent power is
15. When a load resistance is removed from the output of a voltage divider circuit, the
A. 19.52 W C. 275 W
current drawn from the source
B. 195.2 W D. 25 W
A. decreases C. remains the same
B. increases D. is cut off 28. In a series RC circuit, when the frequency and the resistance are halved, the
impedance
16. A 470 W resistor and a 0.2 µF capacitor are in parallel across a 2.5 kHz ac A. doubles
source. The admittance, Y, in rectangular form, is B. is halved
A. 212 W C. 3.14 mS + j2.12 mS C. is reduced to one-fourth
B. 2.12 mS + j3.14 mS D. 318.3 W D. cannot be determined without values

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CERTC Weekly Exam 1 EE Subjects
DC and AC Circuits
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29. A 2 kW resistor is in series with a 0.015 µF capacitor across a 15 kHz ac source. 39. Superposition theorem can be applied only to circuits having ____
What is the magnitude of the total impedance and the phase angle? elements
A. 73.4 W and θ = –19.5° C. 2121 W and θ = –19.5° A. Non-linear C. Linear bilateral
B. 707 W and θ = –19.5° D. 734 W and θ = –38.9° B. Passive D. Resistive
30. In a series RLC circuit that is operating above the resonant frequency, the current: 40. The superposition theorem is essentially based on the concept of
A. lags the applied voltage A. Reciprocity C. Linearity
B. leads the applied voltage B. non-linearity D. Duality
C. is in phase with the applied voltage 41. What are the electrons in motion called?
D. is zero A. Current variation C. Electron velocity
31. A 12 W resistor, a 40 µF capacitor, and an 8 mH coil are in series across an ac B. Electric current D. Dynamic electricity
source. The resonant frequency is 42. Suppose you have an unlimited supply of 1-W, 100 Ω resistors.
A. 28.1 Hz C. 2.810 kHz You need to get a 100 Ω, 10 w resistor. This can be done most
B. 281 Hz D. 10 kHz cheaply by means of a series-parallel matrix of
32. A certain series RLC circuit with a 200 Hz, 15 V ac source has the following A. 3 x 3 resistors C. 4 x 3 resistors
values: R = 12 W, C = 80 µF, and L = 10 mH. The total impedance, expressed in B. 4 x 4 resistors D. 2 x 5 resistors
polar form, is: 43. A material with an excess of 25 x 10^18 electrons loses 6.25 x
A. 12.28 12.34° W C. 9.95 12.34° W 10^18 electrons. The excess electrons are then made to flow past
a given point in 2s. Find the current produced by the resultant
B. 12.57 12.34° W D. 12.62 12.34° W
electron flow.
33. Determine VTH when R1 is 180 and XL is 90 W. A. 2.3 A C. 3 A.
B. 1.5 A D. 3.3 A
44. The resistance of a field winding is 200 ohm at 25 degrees and 250
ohm at 25 degrees. Find the temperature coefficient at 0 degrees
Celsius.
A. 1/275 C. 1/175
B. 1/375 D. None of these
45. The resistance of a winding wire made up of copper at 30°C. What
is the resistance when it operates at a temperature of 75°C.?
assume temperature coefficient at 20°C = 0.004
A. 135 63.4° V C. 12.2 0° V A. 6.7 Ω C. 29.33 Ω
B. 33.33 Ω D. 45.3 Ω
B. 13.5 63.4° V D. 122 0° V
46. A span of wire 1 km long has a conductance of 0.6 S. What is the
34. Referring to the given circuit, find ZTH if R is 15 kW and RL is 38 kW. conductance of a span of this same wire that is 3 km long?
A. 1.8 S C. 0.2 S
B. 0.6 S D. None of these
47. Four resistors R1, R2, R3, R4 are in the ratio 1:2:3:4 are
connected in series with a 30 V battery source. What is the
resistance of R2?
A. 4 C. 16
B. 8 D. Insufficient data
48. Twelve resistors 1 ohm each are arranged along the edge of a
cube with junction at corners. What resistance will be measured
A. 89.82 –51.3° kW C. 9.38 –51.3° kW between terminals of symmetrically opposite corners of a cube?
A. 6/5 ohm C. 5/6 ohm
B. 19.2 –38.3° kW D. 180 –38.3° kW B. 5/9 ohm D. 6/11 ohm
35. Referring to the given figure, determine ZTH as seen by RL if R1 is changed to 3.3 49. Suppose you double the voltage in a simple dc circuit and cut the
kW. resistance in half. The current will
A. Become four times as great
B. Become twice as great
C. Stay the same as it was before
D. Become half as great
50. What is the reciprocal of capacitance?
A. Permeance C. Elastance
B. Reluctance D. daraf
51. How many electrons will pass a fixed point in a 100 W light bulb in
1 hr if the applied constant voltage is 120 V.
A. 1488 –70.7° W C. 5180 –50.5° W
A. 1.87x10^22 C. 2.7x10^22
B. 3859 –31.2° W D. 1828 –50.2° W B. 1.65x10^22 D. None of these
36. The two basic components of a Thevenin equivalent ac circuit are:
52. The resistance of the copper wire at 100°C is 126.48 ohms and
A. the equivalent voltage source and the equivalent series impedance
100 ohms at 30°. Determine the temperature coefficient at 50°C.
B. the equivalent voltage source and the equivalent series resistance
A. 3.517 x 10^3/°C B. 5.317 x 10^-4/°C
C. the equivalent voltage source and the equivalent parallel impedance
D. the equivalent voltage source and the equivalent parallel resistance B. 5.317 x 10^-3/°C D. 3.517 x 10^-3/°C
53. Determine the resistance of an alloy wire at 900°C if its resistance
37. In applying the superposition theorem, is 18 ohms at 40°C and the temperature coefficient is 6.8 x 10^-3
A. the sources are considered one at a time with all others replaced by their at 100°C.
internal impedance A. 195.18 Ω C. 159.18 ohms
B. all sources are considered independently
B. 195.81 Ω D. 951.81 ohms
C. all sources are considered simultaneously
D. the sources are considered one at a time with all others replaced by their 54. The voltage applied across an electric load was reduced by 50
internal resistance percent. The power consumed by the load will be reduced by
38. Kirchhoff’s second Law is based on the law of conservation of A. 25 % C. 35%
A. Charge C. momentum B. 75% D. 50%
B. Energy D. mass

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CERTC Weekly Exam 1 EE Subjects
DC and AC Circuits
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55. A copper transmission line is to be replaced by one of aluminum 70. If admittance is given as: Y = 0.006 – j0.08 mho, then the
having the same total resistance. If the cross sectional area of resistance will be _______
copper wire is 500 MCM, what would be the cross sectional area of A. 25 W C. 52 W
the new aluminum wire? B. 32 W d. nota
A. 800 MCM C. 850 MCM
71. An inductive coil takes a current of 2 A and consumes 160 W when
B. 820 MCM D. 900 MCM
connected to a 240 V AC supply. A second coil when connected
56. If a toaster rated at loo0 W is operated for 30 min, the energy used across the same supply takes 3 A and 500 W. Find the total power
is when the two coils are connected in series to this supply.
A. 0.5 kwh C. 5 kwh A. 144.56 W C. 134.31 W
B. 0.4 kwh D. 0.6 kwh B. 150.22 W D. 128.35 W

57. An alternating voltage of 80 + j60V is applied to a circuit and the 72. What will be the equation for a 25 cycle current sine wave having
current flowing is –4 + j10A. Find the phase angle. an rms value of 30 A?
A. 25 deg C. 50 deg A. 30 sin 25t C. 20 sin 25t
B. 75 deg D. 100 deg B. 42.5 sin 50pt D. none of these
73. An impedance draws a current I = 10 cos (wt - 30°) from a voltage
58. Calculate the susceptance in mho of a circuit consisting of a
v = 220 sin (wt + 30°). What is the impedance?
resistor of 10 ohms in series with a inductor of 0.1 H when the
A. 15.6 – j15.6 C. 19.1 – j11.1
frequency is 50Hz.
B. 15.6 + j15.6 D. 11.0 + j19.1
A. 0.0303 C. 0.0092
B. –0.029 D. 32.95 74. A series RC circuit is connected to a 230 volt 60 cycle source. If
the power taken by the circuit is 4,800 watts and the voltage drop
59. An inductor of negligible resistance and an inductance of 0.07 H is across the resistor is 115 volts, calculate the capacitance of the
connected in series with a resistor of 20 ohms resistance across a capacitor.
200 V, 50Hz supply. Find the maximum value of energy stored in A. 540 µf C. 530 µf
the coil. B. 556 µf D. 503 µf
A. 3.175 J C. 1.585 J
B. 0.236 J D. 0.33 J 75. A 240 V, 25 Hz sinusoidal generator is connected to a 20 ohms
resistor. Determine the instantaneous current when elapsed time
60. The current taken by a circuit is 1.2 A when the applied voltage is is 0.01 second.
250V and the power taken is 135W. What is the power factor? A. 15043A C. 16.30 A
A. 0.45 C. 0.35 B. 16.97 A D. 12.00 A
B. 0.55 D. 0.65 76. Two current sources deliver current to a common load. The first
source delivers a current whose equation is 25 sin 100πt amperes
61. A capacitor connected to a 115V, 25Hz supply takes 5A. What
while the second delivers a current whose equation is 15 cos
current will it take when the capacitance and frequency are
100πt amperes. What is the ms values of the current in the load?
doubled?
A. 29.15 A C. 40 A
A. 2A C. 5A
B. 20.6 A D. 10 A
B. 10A D. 20A
77. Two sources A and B delivers 100A and 150 A, respectively to a
62. The resistor of 20 ohms is connected in parallel with a capacitor load. If these currents are out of phase by 30 electrical degrees,
across a 110 volt 40Hz supply. If the current taken is 6 A, what is determine the total current drawn by the load.
the capacitance. A. 201.5 A C. 250.0 A
A. 88.6 uF C. 68.8 uF B. 215.4 A D. 241.8 A
B. 86.8 uF D. 76.8 uF
78. Across a 230 V, 60 Hz power supply is a 15-ohm non-inductive
63. A reactor of resistance 20 ohms and inductance of 0.1 H is resistor. What is the equation of the resulting current?
connected in parallel with a capacitor. The value of capacitance to A. 21.68 sin 377t C. 26.55 sin 377 t
produce resonance when connected to a 100V, 50 Hz is ____ B. 15.33 sin 377t D. 28.16 sin 377
A. 71.2 uF C. 1.277uF 79. The ratio of W/VA in an AC Circuit means ______.
B. 17.2 uF D. 72.1 Uf A. Power Factor C. Quality Factor
B. Power Quotient D. Load Factor
64. In an R-L series circuit ac circuit R = 10 ohms and XL = 10 ohms.
The phase angle between the applied voltage and circuit current 80. At what frequency will an inductor of 5 mh have the same
will be reactance as a capacitor of 0.1μF?
A. 45 degrees C. 30 degrees A. 7.12 kHz C. 7.12 Hz
B. 60 degrees D. 36.8 degrees B. 7.12 MHz D. 7.12 GHz
81. In a series RLC circuit
65. A circuit when connected to 200V mains takes a current of 20A,
A. Increasing the frequency decreases the resistance
leading the voltage by 1/12 of time period. The circuit resistance is
B. Increasing the frequency increases the resistance
_______.
C. Both XL and XC change as frequency changes
A. 10 ohms C. 8.66 ohms
D. The frequency at which XL = XC
B. 20 ohms D. 17.32 ohms
82. When the power factor of a circuit is zero ______.
66. An RLC circuit is connected to a 200 V ac source. If the Q factor of A. power absorbed is minimum
the coil is 10, then the voltage across C at resonance is B. power absorbed is maximum
A. 200 V C. 2000V C. power absorbed is zero
B. 20V D. 2V D. the impedance is minimum
67. A circuit has an impedance of (1 –j2) ohms. The susceptance of 83. The power dissipated across the resistance in an AC circuit.
the circuit in mho is A. power factor C. true power
A. 0.1 C. 0.2 B. reactive power D. apparent power
B. 0.4 D. none of these
84. In series RLC circuit, R=100Ω, XL=300Ω, and XC=200Ω. The phase
68. What capacitance must be placed in series with an inductance of angle Ø of the circuit is _____.
0.05 H so that when the frequency is 100Hz, the impedance A. 45 C. 90
becomes equal to the ohmic resistance? B. 180 D. 360
A. 70.5 uF C. 50.7 uF
85. A 220 volt, 60 Hz source is driving a series RL circuit. Determine
B. 5.70 uF D. 7.05 uF
the current in the circuit if R=100Ω and XL = 100Ω.
69. An impedance coil takes 10 A and absorbs 250 W when connected A. 1.10 A (lagging) C. 1.55 A (lagging)
across 220 V, 60 Hz source. What power will it absorb when B. 2.20 A (lagging) D. 4.40 A (lagging)
connected across 110 V, 25 Hz mains?
86. The active and reactive powers of an inductive circuit are equal.
A. 539 W C. 239 W
The power factor of the circuit is _____.
B. 439 W D. 339 W
A. 0.8 lagging C. 0.707 lagging
B. 0.6 lagging D. 0.5 lagging

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CERTC Weekly Exam 1 EE Subjects
DC and AC Circuits
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87. The relationship of the voltage across an inductor to its current is
describe as:
A. leading the current by 90 degrees
B. lagging the current by 90 degrees
C. lead the current by 180 degrees
D. in phase with the line current
88. An alternating current whose average value is 1A will produce
_________ 1A dc under similar conditions.
A. less heat than C. the same heat as
B. more heat that D. none of these

89. Thevenin’s theorem is ____ form of equivalent circuit.


A. Voltage C. Both a and b
B. Current D. None of these
90. Norton’s theorem is ____ form of an equivalent circuit.
A. Voltage C. Both a and b
B. Current D. None of these
91. In a pure resistive circuit, the instantaneous voltage and current
are given by:
v = 250 sin 314t i = 10 sin 314t
The peak power in the circuit is _____.
A. 1250W C. 25 W
B. 500 W D. 250 W
92. An R-L series circuit has 15 V across the resistor and 20V across
the inductor. The supply voltage is ____.
A. 35 V C. 5 V
B. 25 V D. 175 V
93. An ac series circuit has R = 6 ohms, XL = 20 ohms, and Xc = 12
ohms. The circuit power factor will be ______.
A. 0.8 lagging C. 0.6 lagging
B. 0.8 leading D. 0.6 leading
94. At series resonance ________.
A. circuit impedance is very large
B. circuit power factor is minimum
C. voltage across L or C is zero
D. circuit power factor is unity
95. At series resonance voltage across the L or C is______.
A. equal to applied voltage
B. equal to voltage across R
C. much more than the applied V
D. less than applied V

96. A 240 V source is connected to a coil of wire that has a resistance


of 7.5 ohms and an inductance of 0.0477 H. Calculate the power
factor of the circuit.
A. 0.385 leading C. 0.385 lagging
B. 0.615 lagging D. 0.615 leading

97. A series resistance-capacitance is connected to a 230 V source. If


the power taken by the circuit is 4,800 watts and the voltage drop
across the resistor is 115 V, find the capacitance of the capacitor.
A. 655 µF C. 544 µF
B. 455 µF D. 555 µF

98. A series RLC circuit consisting of an 80 ohm resistor, a 0.3 H


inductor, and a 50 µF capacitor is connected to a 120V source.
The power factor is
A. 0.7 lagging C. 0.8 lagging
B. 0.8 leading D. 0.9 leading

99. A series RLC circuit consisting of an 80 ohm resistor, a 0.3 H


inductor, and a 50 µF capacitor is connected to a 120V source. For
what value of capacitance will the power factor become 0.8 leading
assuming that impressed voltage, frequency, resistance, and
inductance remain unchanged?
A. 13.5 µF C. 51.3 µF
B. 31.5 µF D. 15.3 µF

100. A 115-volt source is connected to a series circuit consisting of a


fixed resistor and an impedance coil. If the resistor and coil voltage
drops are 55.4 and 80V, respectively, under which value of
resistance and inductance of the impedance coil the current is
1.69 A?
A. R = 20 Ω, L=0.0411 H C. R = 18 Ω, L=0.1328 H
B. R = 18 Ω, L=0.1238 H D. R = 20 Ω, L=0.0114 H

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CERTC Weekly Exam 1 EE Subjects
DC and AC Circuits
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117. In a series circuit, which of the parameters remain constant across all
circuit elements such as resistor, capacitor and inductor etcetera?
101. A load of 250 KVA, operating at a power factor of 0.86 lagging, is
connected to a 2,300 volt ac source. What is the reactive factor?
A. Voltage C. Both voltage and current
A. 0.86 C. 0.51 B. Current D. Neither voltage nor current
B. 0.14 D. 0.68 118. If there are two bulbs connected in series and one blows out, what
102. A series circuit consisting of consisting of a 30 µF capacitor and
Determine the power angle in the series circuit which consists of
happens to the other bulb?
R=25 ohms, L=0.2 H across a power supply of 200 volts, 30 Hz. A. The other bulb continues to glow with the same brightness
A. 36.4º C. 46.4º B. The other bulb stops glowing
B. 52.4º D. 56.4º C. The other bulb glows with increased brightness
103. An inductive loas consisting of R and X in parallel feeding from a D. The other bulb also burns out
2400 Vrms supply absorbs 288KW at a lagging pf of 0.8.
Determine X. 119. What happens to the current in the series circuit if the resistance is
A. 26.667 ohms doubled?
104. What is the reading of a moving iron voltmeter connected across A. It becomes half its original value
the voltage source whose instantaneous value is V(t) B. It becomes double its original value
=10+15cos(377t +60°)
A. 12.25 V C. 10.31 V
C. It becomes zero
B. 8.66 V D. 14.58 V D. It becomes infinity
105. An inductor has a 54 ohm reactance at 60 Hz. What will be the 120. If two bulbs are connected in parallel and one bulb blows out, what
maximum current if this inductor is connected to a 50 Hz source
that produces 100 Vrms.?
happens to the other bulb?
A. 3.13 A A. The other bulb blows out as well
106. An impedance coil has a resistance of 20 ohms an inductive B. The other bulb continues to glow with the same brightness
reactance of 40 ohms. For what value of series resistance will the C. The other bulb glows with increased brightness
overall power factor f the circuit be 0.6? D. The other bulb stops glowing
A. 10 ohms C. 8 ohms
B. 12 ohms D. 5 ohms 121. In a parallel circuit, with a number of resistors, the voltage across
107. The equation of the current in a pure inductor circuit is i= 4.25 each resistor is ________
sin157t when the impressed emf wave is e = 650 cos157t. A. The same for all resistors
determine the equation of the power wave. B. Is divided equally among all resistors
A. P= -1380sin314t C. Is divided proportionally across all resistors
108. An RLC circuit consists of a 55.4 ohm resistor, a 0.17 H inductor,
and an 82.8µF capacitor. If the potential drop across the resistor is D. Is zero for all resistors
72 volts. Calculate the emf of the 60-cycle source. 122. A 15 V source is connected across a 12 Ω resistor. How much energy
A. 83.4 V is used in three minutes?
109. An impedance coil having a resistance of 18 ohms and an
inductance of 0.122 henry is connected in series with a capacitor to
A. 0.938 Wh C. 9.38 Wh
a 117-volt source. What is the value of the capacitor if the circuit B. 93.8 Wh D. 0.0938 Wh
current is 6.5 A?
A. 57.6µF 123. The current in each branch of a parallel circuit is proportional to
110. An RLC circuit has the following R = 200Ω, C = 15μF, L = 230mH, _________
voltage source = 25.46 V. Determine the maximum current. A. The amount of time the circuit is on for
A. Imax=0.116 A C. Imax=0.641 A B. Proportional to the value of the resistors
B. Imax=0.146 A D. Imax=0.164 A
C. Equal in all branches
111. R = 200Ω, XC= 150Ω, XL= 80Ω, Vrms= 120v, f= 60 Hz .How much
capacitance must be added to maximize the power in the circuit D. Proportional to the power in the circuit
(and thus bring it into resonance)?
A. 15.5 micro farad 124. Determine much would it cost to operate a 5.5 kW electric stove for
112. An inductor has a 54 ohm reactance at 60 Hz. What will be the 3.5 hours if it cost P10/kw-hr.
maximum current if this inductor is connected to a 50 Hz source A. P 129.5 C. P 250.6
that produces 100 Vrms?
A. 13.3 A C. 3.14 A B. P 532.4 D. P 192.5
B. 31.85 A D. 2.22
113. When 200 V sinusoidal peak to peak is connected across in ac
voltmeter, it will read ______V
A. 70.7 V
B. 141.4
114. A coil has an inductive reactance of 0.6 H and resistance of 60
ohms. A capacitor of 50 microfarads shunts the coil. Determine the
frequency of the circuit will act as a nonreactive resistance of “R”
ohms.
A. 24.3 Hz
115. Two currenct sources deliver current to a common load. The first
source delivers current whose equation is 25sin100pit amperes.
While the second delivers a current of 12cos 100pit amperes. What
is the rms value of the current in the load?

116. Nodal analysis is generally used to determine______


A. Voltage C. Resistance
B. Current D. Power

CERTC : 0917-3028824 / 0932-175-1218 Page 5

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