Electrical Machines
Direct-on-line (DOL) starters are not suitable for starting large DC motors, because

 the motor may run away.
 the starting torque becomes low.
 the starting current will be enormously high.
 the motor may not start.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
With the increase in speed of a DC motor

 back emf falls and line current increases.
 both back emf as well as line current increase.
 back emf increases but line current falls.
 both back emf as well as line current fall.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Two 3-phase AC generators are such that one has twice the linear dimensions of the other. The field windings of each are excited to give identical sinusoidal air-gap flux density waveform. Both have the same number of stator slots and identical winding patterns. The conductor/slot in a big generator is K times that of the smaller one. The value of K to get equal no load voltage at same frequency is

 4.
  1/2.
 8.
 1/4.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In synchronous generator, inverted V curve is drawn between

 field current on Y-axis and power factor on X-axis
 field current on Y-axis and armature current on X-axis
 field current on X-axis and armature current on Y-axis
 field current on X-axis and power factor on Y-axis

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Due to magnetic saturation, the flux per pole in a DC machine without brush shift

 increases in both the generators and the motors with load.
 decreases in generators and increases in motor with load.
  decreases in both generators and the motors with load.
 increases in generators but decreases in motor with load.

ANSWER DOWNLOAD EXAMIANS APP