ELECTRICAL MACHINE QUIZ

JavaScript isn't enabled in your browser, so this file can't be opened. Enable and reload.

ELECTRICAL MACHINE QUIZ_89

DC MOTOR_02

Q.16 In case of motor, the induced emf is known as

1 point

armature reaction

back emf

reactance voltage

All of the above

Clear selection

Q.17 The back emf oppose the

1 point

terminal voltage

induced emf

applied voltage

circulating current

Clear selection

Q.18 The back emf induced in motor is

1 point

due to motor action

due to generator action

due to engine

all of the above

Clear selection

Q.19 Back emf is also known as

1 point

induced emf

counter emf

generated emf

all of the above

Clear selection

Q.20 The correct expression of back emf is

1 point

Eb = NPфZ/ 60

Eb = NPфZ/ 120A

Eb = NPфZ/ 60A

Eb = NPфZA/ 60

Clear selection

Q.21The back emf of the motor is

1 point

always greater than its terminal voltage

always equal to its terminal voltage

always less than its terminal voltage

any of the above

Clear selection

Q.22 In motor, current flows from the __

1 point

line into the armature to add the generated voltage

armature into the line

line into the armature against the generated voltage

line into the armature to oppose the generated voltage

Clear selection

Q.23 The terminal voltage of the motor is given by

1 point

V = Eb + Ia Ra

V = Eb + Vdrop armature

V = Egen + Ia Ra

Both A and B

[V= motor terminal voltage, E= generated emf, Eb = back emf]

Clear selection

Q.24 When a dc machine is loaded either as a motor or generator, the ___ carry current.

1 point

stater conductor

rotor conductor

field conductor

all of the above

Clear selection

Q.25 In rotor the conductor lie ____ of the rotor at a common radius from its center

1 point

near the centre

near the surface

in between

anywhere

Clear selection

Q.26 The torque produce around the ____ of the rotor and the rotor starts rotating

1 point

radius

diameter

circumference

area

Clear selection

Q.27 When the machine is operates as a generator at constant speed, the torque is

1 point

equal and same as that of provided by the prime-mover

equal and opposite to that of provided by the prime-mover

unequal and same as that of provided by the prime-mover

unequal and opposite to that of provided by the prime-mover

Clear selection

Q.28 The expression of mechanical power developed by the armature is

1 point

Pm = τav

Pm = ωτav

Pm = 2лnτav

Both B and C

Clear selection

Q.29The average torque is given by

1 point

τav = PZф / 2лA

τav = PZфIa / 2A

τav = PZфIa / 2л

τav = PZфIa / 2лA

Clear selection

Q.30which of the following is electrical equivalent of gross mechanical power developed by the armature?

1 point

EIa

I2a Ra

VIa

Clear selection

Submit

Clear form

Forms

This content is neither created nor endorsed by Google.