Related Questions

The losses occurring in a D.C. generator are given below. Which loss is likely to have highest proportion at rated load of the generator?
A Hysteresis loss
B Field copper loss
C Armature copper loss
D Eddy current loss
A laminated iron core has reduced eddy-current losses because
A More wire can be used with less D.C. resistance in coil
B The laminations are insulated from each other
C The magnetic flux is concentrated in the air gap of the core
D The laminations are stacked vertically
Which of the following loss in a D.C. generator varies significantly with the load current?
A Field copper loss
B Windage loss
C Armature copper loss
D None of the above
Under conditions of equal reduced pressure and equal reduced temperature, substances are said to be in the 'corresponding states'. At equal reduced conditions i.e., at the corresponding state, the __________ of different gases are nearly the same.
A Compressibility
B Molecular weight
C Humidity
D None of these
In a D.C. generator all of the following could be the effects of iron losses except
A Loss of efficiency
B Excessive heating of core
C Increase in terminal voltage
D Rise in temperature of ventilating air
In a D.C. generator, the iron losses mainly take place in
A Yoke
B Commutator
C Armature conductors
D Armature rotor
Which of the following components of a D.C, generator plays vital role for providing direct current of a D.C. generator?
A Dummy coils
B Commutator
C Eye bolt
D Equalizer rings
The e.m.f. generated by a shunt wound D.C. generator is E. Now while pole flux remains constant, if the speed of the generator is doubled, the e.m.f. generated will be
A $$\frac{{\text{E}}}{2}$$
B 2E
C Slightly less than E
D E
A separately excited generator as compared to a self-excited generator
A Is amenable to better voltage control
B Is more stable
C Has exciting current independent of load current
D Has all above features
Which of the following losses is not dissipated by the stator core surface in a synchronous motor ?
A Eddy current losses in the conductors
B Iron losses in the stator
C Copper losses in the slot portion of the conductors
D Windage losses

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