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Scott, MIT Graduate
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Looking for penn 4032 alternating current motors, I'm taking

Customer Question

looking for penn foster 4032 alternating current motors
JA: The Tutor can help you get an A on your homework or ace your next test. Tell me more about what you need help with so we can help you best.
Customer: I'm taking a test that i need help
JA: Is there anything else important you think the Tutor should know?
Customer: they have to be familiar with penn foster exams
Submitted: 1 month ago.
Category: Homework
Expert:  SuperiorTutor replied 1 month ago.


Can you please post the questions.


Customer: replied 1 month ago.
1)The practice of interchanging 2 to 3 leads of a running polyphase induction motor is referred to as
A-Slipping B-Synchronizing C- Accelerating D-plugging2) The purpose of a Double-squirrel-cage secondary in an Induction motor is to
A-Create special Current Characteristics
B-Develop minimum torque at Starting speeds
C-reduce primary heating effects
D-produce two rotating magnetic fields3)the starter of a phase wound induction motor consists of a
A-rheostat connected to the secondary
B-reactor connected to the primary
c- compensator in the secondary
d- Series resistance in the primary4) After a sychronous motor has reached the synchronizing speed, the best time to apply the field current is when
A-rotor poles are traveling faster than the stator poles.
B-South stator poles are opposite the south rotor poles
C-induced field current is increasing to a maximum value
D-north rotor poles are directly opposite the south stator pole.5) During the starting of a synchronous motor, the common practice is to
A-Apply d-c field excitation immediately
B-leave the field open-circuited
C-open the circuit of the damper winding
D-place a resistance across the field winding6)to double the rated speed of an 8 pole squirrel-cage motor, the common method is to reconnect the motor as a
A-16 pole C- 4 pole
B-6 pole D- 2 pole7)if a 4-pole 60 hz induction motor has 6% slip normal operation the actual speed is
A-1800 r/min C- 1692r/min
B-1728 r/min D-108 r/min8) to produce a rotating magnetic field for starting a single-phase induction motor the common method is
A-displaced voltage in two windings
B-three field resistors different in value
C-a short-circuited slip ring assembly
D-an autotransformer device.9)if a certain motor develops 10 ft-lb torque with an operating voltage of 110v and is capable of carrying the resulting current at a new voltage of 220v, what is the new torque in foot-pound
A-40 c-5.0
B-20 D-2.510) when A-c voltage is first applied to a large squirrel-cage induction motor and the rotor has not yet begun to rotate there is
A-maximun initial slip
B-full pull-out torque
C-Zero locked-rotor current
D-minimum starting resistance11)the preferred method for applying the field excitation voltage uses a field relay which operates on the principal of
A-thermal Application C-speed application
B-angle Apllication D-time Application12)in the normal operation of an induction motor, the rotor turns at less than synchronous speed in order to
A-develop Circulating currents in the stator frame
B-overcome windage and friction losses
C-produce sufficient voltage to develop the required torque
D-create less heating of the squirrel-cage bars13)If a 5 hp three phase induction motor operates on a 230v system with an efficiency of 93.5% and a power factor of 80% at normal operation, what is the current in amperes (approximately)?
A-21.7 C-11.7
B-12.5 D-1014)To drive a 1000-hp load at unity power factor and constant speed. the recommended type of A-C motor is the
A-polyphase Synchronous type
B-Single-Phase induction Type
C-Polyphase induction type
D-single-phase synchronous type15)which of the following is the true of the operation of a synchronous motor
A-it develops full slip at synchronous speed
B-it is started by the amortisserur winding
C-it has an open-circuit field winding
D-it is started by applying direct current16)the type of induction motor enclosure preferred for installation in a moist and corrosive atmosphere is the
A-splashproof motor
B-open Dripproof motor
C-weather-protected type I motor
D-totally enclosed fan-cooled motor17) A synchronous motor operating at unity power factor on a 550v circuit has a rated field current of 12A and pull-out torque of 160%. if the line voltage drops to 500v and the field current decreases to 10A. what is the approximate maximum load, in percent, that the machine can carry for 1 min?
A-174.48% C-121.21%
B-145.45% D-75.75%18)if a Synchronous motor rated at 80% leading power factor operates 50% load, what is the armature current, expressed in percent of rated value ?
A-66% C-47%
B-54% D-38%19) The total load of Industrial Plant is 4000 KW, and the load operates at a power factor of 0.85 lag. if an 800-HP synchronous motor with 93.5% rated efficiency and operating at unity power factor is added, what is the new value of power factor in Percent?
A-98.6% C-88.2%
B-89.5% D-76.0%20) the type of motor often used for ship propulsion application is the
A-synchronous Motor
B-Shaded-pole Motor
C-Repulsion Motor
D-induction Motor.

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