Q1:-The highest speed attainable by dc shunt motors is
1.
Much higher than no loads speed
2.
Much lower than no load speed
3.
ideally infinite
4.
Equal to
no load speed
ANSWER:-4
Q2:-A lap wound dc generator having 250. Armature conductor
runs at 1200rpm if the generated emf is 200 V then the operating flux of the dc
generator is
1.
0.08 Wb
2.
0.04 Wb
3.
0.06 Wb
4.
0.02Wb
ANSWER:-2
Q3:-which of the following is correct
1.
The effect of air gap flux on armature current
of a synchronous m/c is called armature reaction
2.
The efficiency of current on main flux of a
synchronous m/c is called armature reaction
3.
The efficiency of armature current on air gap
flux of a synchronous m/c is called armature reaction
4.
The efficiency
of field current on main flux of a synchronous m/c is called armature
reaction
ANSWER:-2
Q4:- If the starting torque of a 3-phase I.M. Tst for DOL
starting that for star delta starting of
the same motor is
1.
Tst/3
2.
3Tst
3.
Root 3 Tst
4.
Tst/root 3
ANSWER:-1
Q5:- The motor characteristics best suited for traction
purpose are those of
1.
Dc series motor
2.
Synchronous motor
3.
Induction motor
4.
Dc shunt motor
ANSWER:-1
Q6:- Star- delta stating of 3-phase of I.M. the starting
voltage is reduced to
1.
Root 3 times of normal voltage
2.
3 times of normal voltage
3.
1/3 times of normal voltage
4.
(1/root 3 ) times of normal voltage
ANSWER:-4
Q7:-Which of the following does not employ a null method of
measurement
1.
Megger
2.
Dc potentiometer
3.
Kelvin double bridge
4.
Ac potentiometer
ANSWER:-1
Q8:-Megger is an instrument by which we can measure
1.
High resistance
2.
Low resistance
3.
High current
4.
High voltage
ANSWER:-1
Q9:- With the decrease in the strength of the permanent
magnet in an insulator megger due to ageing the megger reading will
1.
Be lower than actual
2.
Be higher than actual
3.
Remain unaffected
4.
Fluctate
rapidly
ANSWER:-1
Q10:- The burden of current transformer is expressed in
1.
Watt
2.
VA
3.
Rated secondary current
4.
Voltage ating of secondary
ANSWER:-2
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