What will be the frequency of a three-phase, six pole, AC generator operating at 1800 revolutions per minute? A. 60 hertz B. 90 hertz C. 120 hertz D. 180 hertz

What will be the frequency of a three-phase, six pole, AC generator operating at 1800 revolutions per minute? A. 60 hertz B. 90 hertz C. 120 hertz D. 180 hertz
by

1 Answer

Answer :

Answer: B
by

Related questions

The prime mover of an AC two pole main propulsion generator drives the generator at 3600 RPM. If the main propulsion motor has 80 poles, what will be the propeller speed? A. 45 RPM B. 80 RPM C. 90 RPM D. 180 RPM

Description : The prime mover of an AC two pole main propulsion generator drives the generator at 3600 RPM. If the main propulsion motor has 80 poles, what will be the propeller speed? A. 45 RPM B. 80 RPM C. 90 RPM D. 180 RPM

Last Answer : Answer: C

The unit 'hertz' is equivalent to _____________. A. coulombs per second B. revolutions per second C. revolutions per minute D. cycles per second

Description : The unit 'hertz' is equivalent to _____________. A. coulombs per second B. revolutions per second C. revolutions per minute D. cycles per second

Last Answer : Answer: D

A four-pole 60-hertz induction motor has a synchronous speed of 1800 RPM and a slip of 4 percent at full load. What will be its full load speed? A. 1728.0 RPM B. 1730.7 RPM C. 1800.0 RPM D. 1872.0 RPM

Description : A four-pole 60-hertz induction motor has a synchronous speed of 1800 RPM and a slip of 4 percent at full load. What will be its full load speed? A. 1728.0 RPM B. 1730.7 RPM C. 1800.0 RPM D. 1872.0 RPM

Last Answer : Answer: A

If there is a reduction in the normally supplied frequency to a 120/240 volt, threephase AC current motor from 60 hertz to 55 hertz, the motor would _____________. A. run at a slower speed B. operate at a lower current C. overheat D. trip off the line

Description : If there is a reduction in the normally supplied frequency to a 120/240 volt, threephase AC current motor from 60 hertz to 55 hertz, the motor would _____________. A. run at a slower speed B. operate at a lower current C. overheat D. trip off the line

Last Answer : Answer: A

An electrical component is connected across a 120 volt 60 hertz AC supply. What is the current drawn by the component if the impedance is 200 ohms? A. 0.01 amperes B. 0.60 amperes C. 1.67 amperes D. 100 amperes

Description : An electrical component is connected across a 120 volt 60 hertz AC supply. What is the current drawn by the component if the impedance is 200 ohms? A. 0.01 amperes B. 0.60 amperes C. 1.67 amperes D. 100 amperes

Last Answer : Answer: B

The difference between the synchronous speed of an induction machine and its operating speed (slip) may be correctly expressed _____________. A. as a percent of synchronous speed B. as a decimal fraction of synchronous speed C. directly in revolutions per minute D. as all of the above

Description : The difference between the synchronous speed of an induction machine and its operating speed (slip) may be correctly expressed _____________. A. as a percent of synchronous speed B. as a decimal fraction of synchronous speed C. directly in revolutions per minute D. as all of the above

Last Answer : Answer: A

The output voltage of a 440 volt, 60 hertz, AC generator is controlled by the _____________. A. prime mover speed B. exciter output voltage C. load on the alternator D. number of poles

Description : The output voltage of a 440 volt, 60 hertz, AC generator is controlled by the _____________. A. prime mover speed B. exciter output voltage C. load on the alternator D. number of poles

Last Answer : Answer: B

An AC generator produces 60 Hz at 1800 RPM. If the generator speed is increased to 1830 RPM, the cycles will _____________. A. remain at 60 Hz B. increase to 61 Hz C. decrease to 59 Hz D. increase to 63 Hz

Description : An AC generator produces 60 Hz at 1800 RPM. If the generator speed is increased to 1830 RPM, the cycles will _____________. A. remain at 60 Hz B. increase to 61 Hz C. decrease to 59 Hz D. increase to 63 Hz

Last Answer : Answer: B

An electric heating element supplied with 120 volts draws 15 amps. How much power will be consumed? A. 15 watts B. 45.57 watts C. 180 watts D. 1800 watts

Description : An electric heating element supplied with 120 volts draws 15 amps. How much power will be consumed? A. 15 watts B. 45.57 watts C. 180 watts D. 1800 watts

Last Answer : Answer: D

What will be the phase angle relationship of a six-pole, three-phase, rotating field generator? A. 60° B. 120° C. 180° D. 360°

Description : What will be the phase angle relationship of a six-pole, three-phase, rotating field generator? A. 60° B. 120° C. 180° D. 360°

Last Answer : Answer: B

A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train? a) 120 meters b) 180 meters c) 324 meters d) 150 meters

Description : A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train? a) 120 meters b) 180 meters c) 324 meters d) 150 meters

Last Answer : d) 150 meters

An 8 pole wound rotor induction motor operating on 60 Hz supply is driven at 1800 r.p.m. by a prime mover in

Description : An 8 pole wound rotor induction motor operating on 60 Hz supply is driven at 1800 r.p.m. by a prime mover in the opposite direction of revolving magnetic field. The frequency of the rotor current is (a) 30 Hz (b) 60 Hz (c) 120 Hz (d) 180 Hz 

Last Answer : 30 Hz As the frequency of the rotor is given by  F= N*P/120 so from the above equation the frequency of the rotor current can be easily calculated  i.e. 1800×8/120=30 Hence the required value of rotor frequency is 30 Hz

A four-pole induction motor, operating on three-phase 60 cycle current will operate at approximately ___________. A. 850 RPM B. 1,150 RPM C. 1,750 RPM D. 3,550 RPM

Description : A four-pole induction motor, operating on three-phase 60 cycle current will operate at approximately ___________. A. 850 RPM B. 1,150 RPM C. 1,750 RPM D. 3,550 RPM

Last Answer : Answer: C

What is the frequency of an alternator which has 2 poles and makes 3600 revolutions per minute?

Description : What is the frequency of an alternator which has 2 poles and makes 3600 revolutions per minute? A) 3600 HZ B) 60 Hz C) 120 Hz D) None of these

Last Answer : What is the frequency of an alternator which has 2 poles and makes 3600 revolutions per minute? A) 3600 HZ B) 60 Hz C) 120 Hz D) None of these

Revenue from services with duration of not more than……….. days to be recognized when rendering of services under contract is completed or substantially complted. a) 60 days b) 90 days c) 120 days d) 180 days

Description : Revenue from services with duration of not more than……….. days to be recognized when rendering of services under contract is completed or substantially complted. a) 60 days b) 90 days c) 120 days d) 180 days

Last Answer : b) 90 days

The missing number in the series 40, 120, 60, 180, 90, ?, 135 is (A) 110 (B) 270 (C) 105 (D) 210

Description : The missing number in the series 40, 120, 60, 180, 90, ?, 135 is (A) 110 (B) 270 (C) 105 (D) 210

Last Answer : Answer: B

Assuming a standard 60 Hz. input to the circuit shown in the illustration, the ripple frequency would be ____________. EL-0085 A. 30 Hz B. 60 Hz C. 90 Hz D. 120 Hz

Description : Assuming a standard 60 Hz. input to the circuit shown in the illustration, the ripple frequency would be ____________. EL-0085 A. 30 Hz B. 60 Hz C. 90 Hz D. 120 Hz

Last Answer : Answer: D

At resonance the phase angle is equal to A 0 0B 180 0 C 120 0 D 90 0

Description : At resonance the phase angle is equal to A 0 0B 180 0 C 120 0 D 90 0

Last Answer : D 90 0

Which of the listed sections of an emergency switchboard is used to supply power for alarm signals under emergency conditions? A. The generator and bus transfer section B. The 450 volt, 60 cycle, 3 phase bus C. The 120 volt, 3 phase, 60 cycle bus D. The 24 volt DC bus

Description : Which of the listed sections of an emergency switchboard is used to supply power for alarm signals under emergency conditions? A. The generator and bus transfer section B. The 450 volt, 60 cycle, 3 phase bus C. The 120 volt, 3 phase, 60 cycle bus D. The 24 volt DC bus

Last Answer : Answer: D

If the synchronous speed of a 12 pole, polyphase, induction motor operating at 60 Hz were 600 RPM, how many poles will be required in a similar motor operating at the same frequency but having a synchronous speed of 900 RPM? A. 4 B. 6 C. 8 D. 18

Description : If the synchronous speed of a 12 pole, polyphase, induction motor operating at 60 Hz were 600 RPM, how many poles will be required in a similar motor operating at the same frequency but having a synchronous speed of 900 RPM? A. 4 B. 6 C. 8 D. 18

Last Answer : Answer: C

To increase the frequency of an operating AC generator, you should ____________. A. increase the field excitation B. decrease the field excitation C. increase the number of magnetic poles D. increase the speed of the prime mover

Description : To increase the frequency of an operating AC generator, you should ____________. A. increase the field excitation B. decrease the field excitation C. increase the number of magnetic poles D. increase the speed of the prime mover

Last Answer : Answer: D

The voltage of an operating AC turbogenerator is raised or lowered by adjusting the _____________. A. exciter generator governor controls B. synchronizing switch C. phase sequence switch D. generator field exciter

Description : The voltage of an operating AC turbogenerator is raised or lowered by adjusting the _____________. A. exciter generator governor controls B. synchronizing switch C. phase sequence switch D. generator field exciter

Last Answer : Answer: D

Which of the listed classes of electrical insulation is suited for the highest operating temperature? A. Class 90 (O) B. Class 105 (A) C. Class 130 (B) D. Class 180 (H)

Description : Which of the listed classes of electrical insulation is suited for the highest operating temperature? A. Class 90 (O) B. Class 105 (A) C. Class 130 (B) D. Class 180 (H)

Last Answer : Answer: D

A turbogenerator has a rated output of 1200 KW at 60 Hertz, with a no load frequency of 61.5 Hertz. What is its speed droop? A. 1.03% B. 1.50% C. 2.44% D. 2.50%

Description : A turbogenerator has a rated output of 1200 KW at 60 Hertz, with a no load frequency of 61.5 Hertz. What is its speed droop? A. 1.03% B. 1.50% C. 2.44% D. 2.50%

Last Answer : Answer: D

An alternator is being paralleled with one on the line. At the INSTANT the circuit breaker is closed, the frequency of the incoming alternator will normally _____________. A. increase B. not change C. decrease D. be exactly 60 hertz

Description : An alternator is being paralleled with one on the line. At the INSTANT the circuit breaker is closed, the frequency of the incoming alternator will normally _____________. A. increase B. not change C. decrease D. be exactly 60 hertz

Last Answer : Answer: C

If three AC generators are operating in parallel, and one of them were to 'pull out' of synchronism with the other two generators, the ____________. A. normally operating AC generators will vibrate severely B. AC generator pulling out of synchronism will vibrate severely C. normally operating AC generators will overspeed and unload D. AC generator pulling out of synchronism will become motorized

Description : If three AC generators are operating in parallel, and one of them were to 'pull out' of synchronism with the other two generators, the ____________. A. normally operating AC generators will ... AC generators will overspeed and unload D. AC generator pulling out of synchronism will become motorized

Last Answer : Answer: B

A two-phase generator is connected to two 9012 load resistors. Each coil generates 120 V ac. The value of ...

Description : A two-phase generator is connected to two 90Ω load resistors. Each coil generates 120 V ac. The value of current flowing through the common neutral line will be: A. 1.33 A B. 1.88 A C. 2.66 A D. 1.77 A

Last Answer : A two-phase generator is connected to two 90Ω load resistors. Each coil generates 120 V ac. The value of current flowing through the common neutral line will be: 1.77 A

How to calculate the rate of rotation, in revolutions per minute.

Description : How to calculate the rate of rotation, in revolutions per minute.

Last Answer : answer:I’m going with 1.56 revs/min. Circumference = pi*d = 376.8 m Rate of rotation = 9.8 m/s, so it takes 38.4s to complete one rev. 60/38.4 = 1.56

is the measure of whether a plant is now using more or less energy to manufacture its product than it did in the past. a) Total Dissolved Solids (TDS). c) Plant Energy Performance (PEP) b) Revolutions Per Minute (RPM) d) Option (a) and (b)

Description : is the measure of whether a plant is now using more or less energy to manufacture its product than it did in the past. a) Total Dissolved Solids (TDS). c) Plant Energy Performance (PEP) b) Revolutions Per Minute (RPM) d) Option (a) and (b)

Last Answer : Plant Energy Performance (PEP)

is the measure of whether a plant is now using more or less energy to manufacture its product than it did in the past. a) Total Dissolved Solids (TDS) b) Plant Energy Performance (PEP) c) Revolutions Per Minute (RPM) d) Option (a) and (b)

Description : is the measure of whether a plant is now using more or less energy to manufacture its product than it did in the past. a) Total Dissolved Solids (TDS) b) Plant Energy Performance (PEP) c) Revolutions Per Minute (RPM) d) Option (a) and (b)

Last Answer : Plant Energy Performance (PEP)

A four pole turbogenerator is used in conjunction with a 160 pole propulsion motor. If the generator is turning at 3,200 RPM, what is the current speed of the propeller? A. 40 RPM B. 60 RPM C. 80 RPM D. 100 RPM

Description : A four pole turbogenerator is used in conjunction with a 160 pole propulsion motor. If the generator is turning at 3,200 RPM, what is the current speed of the propeller? A. 40 RPM B. 60 RPM C. 80 RPM D. 100 RPM

Last Answer : Answer: C

A four pole, 60 Hz, three-phase synchronous motor comes up to 1760 RPM when started as an induction motor. What is the percent slip after the rotor field is energized? A. 0 B. 1.1 C. 2.2 D. 3.3

Description : A four pole, 60 Hz, three-phase synchronous motor comes up to 1760 RPM when started as an induction motor. What is the percent slip after the rotor field is energized? A. 0 B. 1.1 C. 2.2 D. 3.3

Last Answer : Answer: A

A network with bandwidth of 10 Mbps can pass only an average of 15,000 frames per minute with each frame carrying an average of 8,000 bits. What is the throughput of this network? a. 2 Mbps b. 60 Mbps c. 120 Mbps

Description : A network with bandwidth of 10 Mbps can pass only an average of 15,000 frames per minute with each frame carrying an average of 8,000 bits. What is the throughput of this network? a. 2 Mbps b. 60 Mbps c. 120 Mbps

Last Answer : a. 2 Mbps

A network with bandwidth of 10 Mbps can pass only an average of 15,000 frames per minute with each frame carrying an average of 8,000 bits. What is the throughput of this network ? (A) 2 Mbps (B) 60 Mbps (C) 120 Mbps (D) 10 Mbps

Description : A network with bandwidth of 10 Mbps can pass only an average of 15,000 frames per minute with each frame carrying an average of 8,000 bits. What is the throughput of this network ? (A) 2 Mbps (B) 60 Mbps (C) 120 Mbps (D) 10 Mbps

Last Answer : (A) 2 Mbps Explanation: In data transmission, throughput is the amount of data moved successfully from one place to another in a given period of time, and typically measured in bits per second (bps), ... second (Mbps) or gigabits per second (Gbps). Here, Throughput = 15000 x 8000/60 = 2 Mbps 

Nesha scored 120 out of 150 in English, 120 out of 180 in mathematics and 160 out of 200 in Science. Find Nesha’s score as percentage: (i) in Mathematics (ii) in all the three subjects (on the whole). a) 66 2/3, 78 22/51 b) 71 23/5, 45 7/31 c) 54 13/33, 82 3/4 d) 60 3/4, 76 32/41

Description : Nesha scored 120 out of 150 in English, 120 out of 180 in mathematics and 160 out of 200 in Science. Find Nesha’s score as percentage: (i) in Mathematics (ii) in all the three subjects (on the whole). a) 66 2/3, 78 22/51 b) 71 23/5, 45 7/31 c) 54 13/33, 82 3/4 d) 60 3/4, 76 32/41 

Last Answer :  Answer: A (i) Percentage scored in Mathematics = 120/180 100  = 12000/180  =1200/18  = 66 2 /3 % (ii) Total maximum of all the three subjects = 150 + 160 + 200 = 510 and Total score in the ... percentage on the whole = (400/510 100)  = (40000/510)  = 4000/51  = 78 22/51 %

Which of the following procedures should be used to determine the load of a threephase, delta wound, AC generator? A. Multiply the amperage in one phase by three. B. Divide the total amperage in all phases by three. C. Multiply the amperage in one phase by the square root of three. D. Divide the total amperage in all phases by the square root of three.

Description : Which of the following procedures should be used to determine the load of a threephase, delta wound, AC generator? A. Multiply the amperage in one phase by three. B. Divide the total amperage in all ... square root of three. D. Divide the total amperage in all phases by the square root of three.

Last Answer : Answer: C

A 6 pole 3-phase wound-rotor induction machine is driven by another machine at 1800 rpm. The rotor of the ...

Description : A 6 pole 3-phase wound-rotor induction machine is driven by another machine at 1800 rpm. The rotor of the induction machine is connected to a 50Hz system. If the mechanical rotation of the rotor is in the same direction as the rotor winding flux rotation, then frequency of the stator voltage will be

Last Answer : A 6 pole 3-phase wound-rotor induction machine is driven by another machine at 1800 rpm. The rotor of the induction machine is connected to a 50Hz system. If the mechanical rotation of ... the same direction as the rotor winding flux rotation, then frequency of the stator voltage will be 140 Hz.

The angle between spring force and damping force is A 180 0 B 120 0 C 90 0 D 0 0

Description : The angle between spring force and damping force is A 180 0 B 120 0 C 90 0 D 0 0

Last Answer : C 90 0

Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels. (A) 90 (B) 120 (C) 150 (D) 180

Description : Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels. (A) 90 (B) 120 (C) 150 (D) 180

Last Answer : (B) 120

The electrical schematic shown in the illustration indicates the lighting feeder circuit is _____________. EL-0014 A. three phase, 450 volt, and 60 cycle B. three phase, 120 volt, and 60 cycle C. single phase, 120 volt, and 60 cycle D. not specified

Description : The electrical schematic shown in the illustration indicates the lighting feeder circuit is _____________. EL-0014 A. three phase, 450 volt, and 60 cycle B. three phase, 120 volt, and 60 cycle C. single phase, 120 volt, and 60 cycle D. not specified

Last Answer : Answer: A

What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is

Description : What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is rotating at speed of 1140 rpm? A) 60% B) 5% C) 10% D) None of these

Last Answer : What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is rotating at speed of 1140 rpm? A) 60% B) 5% C) 10% D) None of these

Which of the listed motors will operate at the highest RPM, assuming that each operates at the same frequency? A. A four-pole synchronous motor under normal load. B. A four-pole induction motor under no load. C. A six-pole synchronous motor under normal load. D. A six-pole induction motor under full load.

Description : Which of the listed motors will operate at the highest RPM, assuming that each operates at the same frequency? A. A four-pole synchronous motor under normal load. B. A four-pole induction motor under ... A six-pole synchronous motor under normal load. D. A six-pole induction motor under full load.

Last Answer : Answer: A

What is the rotor speed of a four pole, 60 cycle, induction motor operating at full load with 3% slip? A. 270 RPM B. 540 RPM C. 873 RPM D. 1746 RPM

Description : What is the rotor speed of a four pole, 60 cycle, induction motor operating at full load with 3% slip? A. 270 RPM B. 540 RPM C. 873 RPM D. 1746 RPM

Last Answer : Answer: D

Which type of AC single-phase motor will also operate on direct current? A. Split-phase B. Series-wound C. Shaded-pole D. Repulsion-start

Description : Which type of AC single-phase motor will also operate on direct current? A. Split-phase B. Series-wound C. Shaded-pole D. Repulsion-start

Last Answer : Answer: B

The number of cycles per second occurring in AC voltage is known as the _____________. A. phase angle B. frequency C. wave form D. half mode

Description : The number of cycles per second occurring in AC voltage is known as the _____________. A. phase angle B. frequency C. wave form D. half mode

Last Answer : Answer: B

One single-phase energy meter operating on 230 V and 5 A for 5 hours makes 1940 revolutions. Meter...

Description : One single-phase energy meter operating on 230 V and 5 A for 5 hours makes 1940 revolutions. Meter constant is 400 rev/kWh. The power factor of the load is

Last Answer : One single-phase energy meter operating on 230 V and 5 A for 5 hours makes 1940 revolutions. Meter constant is 400 rev/kWh. The power factor of the load is 0.8

An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. cause the slip rings to melt C. cause a low voltage differential to develop between the armature and the bus D. cause high currents to be induced in the field windings

Description : An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. ... between the armature and the bus D. cause high currents to be induced in the field windings

Last Answer : Answer: D

A loss of field excitation to an AC generator while operating in parallel will cause it to ____________. A. absorb more and more load due to decreased armature reaction B. lose its load due to the inherent speed droop built into the governor C. smoke and overload due to field flashover as residual field flux changes polarity D. lose its load, begin to motorize, trip out on reverse power relay, and possibly overspeed

Description : A loss of field excitation to an AC generator while operating in parallel will cause it to ____________. A. absorb more and more load due to decreased armature reaction B. lose its load due to ... polarity D. lose its load, begin to motorize, trip out on reverse power relay, and possibly overspeed

Last Answer : Answer: D

The power factor of an AC generator operating singularly is determined by the __________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage

Description : The power factor of an AC generator operating singularly is determined by the __________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage

Last Answer : Answer: A

The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels. (A) 60(B) 90 (C) 105 (D) 120

Description : The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels. (A) 60 (B) 90 (C) 105 (D) 120

Last Answer : (B) 90