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50 Cards in this Set
- Front
- Back
- 3rd side (hint)
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The number of cycles of an ac voltage is known as A. Frequency B. Wave form C. Phase angle D. Half mode |
A. Frequency |
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One joule of electrical energy is equivalent to _____. A. One watt-second B. One watt-minute C. One kilowatt-hour D. One watt per second |
A. One watt-second |
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Which of the following motors is well adapted to start large heavy inertia loads? A. Series wound motor B. Repulsion induction motor C. Shunt motor D. Stepper motor |
A. Series wound motor |
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Three horsepower is equivalent to _____ kilowatts. A. 0.764 B. 2.238 C. 0.764 D. 2.292 |
B. 2.238 |
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A diode has a specified PIV rating. What do you mean by PIV? A. Peak instantaneous voltage B. Peak insulation voltage C. Peak inverse voltage D. Peak input voltage |
C. Peak inverse voltage |
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A circuit has a capacitance of 35 microfarad and an inductance of 0.2 H. Calculate the resonant frequency of the circuit. A. 65 Hz B. 60 Hz C. 50 Hz D. 55 Hz |
B. 60 Hz |
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Which of the following dc motors is used in high-speed applications such as in compressors, blowers, fans, etc.? A. Series motor B. Shunt motor C. Cumulative compound motor D. Differential compound motor |
D. Differential compound motor |
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Core loss on electrical machine is the same term as _____. A. Copper loss B. Iron loss C. Windage loss D. Exciter loss |
B. Iron loss |
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Brushes are made from _____. A. Lead B. Carbon C. Silver D. Copper |
B. Carbon |
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The process of adding impurities to a pure semiconductor. A. Bonding B. Charging C. Doping D. Energizing |
C. Doping |
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DPDT stands for A. Double pole duplex switch B. Double pole double throw switch C. Duplex switch D. None of these |
B. Double pole double throw switch |
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Introduction type single-phase energy meter is A. An ampere-hour meter B. A wattmeter C. A true watt-hour meter D. None of these |
C. A true watt-hour meter |
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Which of the following machines is commonly used to drive lifting machines? A. Squirrel cage introduction motor B. Dc series motor C. Repulsion type introduction motor D. Dc compound motor |
B. Dc series motor |
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If a motor is to be controlled from five different locations, how many and what types of switches are to be used? A. Three 4-way and two 3-way switches B. One 4-way and three 3-way switches C. One 3-way and four 4-way switches D. None of these |
A. Three 4-way and two 3-way switches |
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Wound rotor motors are usually started by the use of what type of starter? A. Primary resistance starter B. Autotransformer starter C. Wye-delta starter D. Secondary resistance starter |
D. Secondary resistance starter |
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A 230-V, 60 Hz motor is connected to a 230-V, 50 Hz electrical system. What happens? A. The appliance draws more current B. The appliance will not operate C. The appliance draws lesser current D. The appliance draws the same current |
A. The appliance draws more current |
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Which of the following is an advantage of dc motors over ac motors? A. They have higher allowable speeds B. They can lift heavier loads C. They have better speed control over a wide range D. They have a longer life |
C. They have better speed control over a wide range |
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To transmit power economically over considerable distances, it is necessary that the voltage be high. High voltages are readily obtainable with A. Rectifier currents B. Dc currents C. Carrier currents D. Ac currents |
D. Ac currents |
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A passive element in a circuit is the one that _____ the energy A. Supplies B. Receives C. Relays D. Transmits |
B. Receives |
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Separators in a storage battery are used to prevent the plates from _____. A. Touching the container B. Touching the electrolyte C. Shorting together D. None of these |
C. Shorting together |
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An RME may install electrical system in excess of 500kVA or in excess of 600 volt provided I. He is a holder of a BSEE degree II. He is more than 5 years of electrical installation experience III. He shall be under the supervision of a PEE or REE A. I and II B. II C. III D. I, II and III |
C. III |
C. III |
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What is the electrolyte in a lead-acid storage battery? A. H2O2 B. HCl C. H2SO4 D. HgSO4 |
C. H2SO4 |
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A staircase lamp is to be controlled at three different locations. What switches would an electrician install? A. Two SPST and one 3-way switches B. Two 3-way and one 4-way switches C. Two 3-way and one SPST switches D. Two 4-way and one SPST switches |
B. Two 3-way and one 4-way switches |
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The unit of magnetic flux in SI. A. Tesla B. Volt-ampere C. Maxwell D. Weber |
D. Weber |
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The electric device which blocks dc but allows ac. A. Rectifier B. Inverter C. Capacitor D. Inductor |
C. Capacitor |
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The resistance of a circuit containing 1 ohm, 2 ohms, and 3 ohms in parallel is _____. A. 6 ohms B. 5.45 ohms C. 0.545 ohm D. 4.5 ohms |
C. 0.545 ohms |
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A parallel circuit is one that has A. All elements connected end to end B. Same current flowing through all elements C. All elements connected across the power supply so that removing one element does not stop the others from working D. All elements side by side |
C. All elements connected across the power supply so that removing one element does not stop the others from working |
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In dc circuits, the power is expressed as the product of which of the following? A. Coulombs and amperes B. Amperes and ohms C. Amperes and volts D. Coulombs and volts |
C. Amperes and volts |
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If the series field is connected in series with the armature, and the shunt field is connected across the combination, what type of dc generator is this? A. Shunt B. Series C. Long shunt compound D. Short shunt compound |
C. Long shunt compound
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An instrument that measures the electrical pressure in a circuit A. Ammeter B. Megger C. Galvanometer D. Voltmeter |
D. Voltmeter |
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A lubricant to make pulling of wires or cables through the conduit easier A. Grease B. Resin C. Talc D. Iron fillings |
C. Talc |
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Give an example of an electrical conductor. A. Brass B. Asbestos C. Slate D. Latex
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A. Brass |
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The three special types of gears used in gearmotors are helical, spur and worm. Which of the types mentioned above is best in high power applications? A. Helical B. Spur C. Worm D. All of these |
B. Spur |
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The output voltage of a single loop generator is a A. Steady dc B. Steady ac C. Pulsating ac D. Pulsating dc |
C. Pulsating ac |
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How would you determine, from visual observation of the armature winding, whether a generator is lap or wave wound? A. Connection to the field winding B. Connection to the communicator C. Connection to the brushes D. The direction of the end connection |
B.Connection to the communicator |
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What classification is given to a dc generator that receives its field excitation current from external source? A. Self-excited B. Controlled excitation C. Separately excited D. Internally excited |
A. Self-excited |
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A dc generator supplies a load resistance 1.4 ohms through a pair of wires having a total resistance of 0.10 ohm. The voltage at the dc generator terminals is 120 V, what is the voltage across the load? A. 110 V B. 112 V C. 105 V D. 115 V |
B. 112 V |
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Find the voltage regulation of a generator when full-load voltage is 110 v and no-load voltage is 120 V. A. 1% B. 9.09% C. 90.9% D. 10% |
B. 9.09% |
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The shunt field of a compound generator is connected across both the series and the armature. This connection is known as A. Short shunt B. Long shunt C. Differential compound D. Cumulative compound |
B.Long shunt |
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A 25-hp engine drives a dc generator, if the generator has an efficiency of 90%, how much does it deliver? A. 22.5 hp B. 21 hp C. 24 hp D. 25 hp |
A. 22.5 hp |
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Residual magnetism is necessary in a A. Separately excited generator B. Self-excited generator C. Both of these D. None of these |
A. Separately excited generator |
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If a commutator is dirty, clean using A. Sandpaper B. Emery C. Cloth D. Oil |
B. EmeryB |
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It is the power required to drive the unexcited dc machine at normal speed with its brushes lifted A. Friction and windings loss B. Brush friction loss C. Exciter loss D. Ventilation loss |
A. Friction and windings loss |
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In starting a 500 hp, 2300-volt, 3-phase synchronous motor the field winding is initially short circuited so as to A. Produce much larger starting torque B. Lower voltage produced b/w the layers of the field winding C. Increased induced voltage in field winding D. Provide better flux distribution in the air gap |
B. Lower voltage produced b/w the layers of the field winding |
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In parallel operation of alternator, if the excitation of one alternative is changer it will only change A. Real power taken by the machine B. Reactive power taken by the machine C. Apparent power taken by the machine D. Synchronizing power of the machine |
B.Reactive power taken by the machine |
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For parallel operation of dc generators A. The frequency must be the same B. The voltage must be the same C. Phase sequence must be the same D. Speed must be the same |
B.the voltage must be the same |
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For parallel operation of dc generators A. The frequency must be the same B. The voltage must be the same C. Phase sequence must be the same D. Speed must be the same |
B.the voltage must be the same |
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The simplest form of motor controller is A. Toggle switch B. Drum switch C. Magnetic switch D. Relay |
A. Toggle switch |
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Another name for a magnetic starter is a A. Manual switch B. Contactor C. Manual starter D. Magnetic control |
C.Manual starter |
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A 2-pole ac generator is running at 1,500 rpm. What is the frequency? A. 25 Hz B. 50 Hz C. 60 Hz D. None of these |
A. 25 Hz |
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