Electrical Machines What is the increase in the torque expressed as percentage of initial torque, if current drawn by the dc series motor is increased from 10A to 11A? 41% 11% 10% 21% 41% 11% 10% 21% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the field-flux axis and armature-mmf axis are respectively along quadrature axis and direct axis direct axis and indirect axis quadrature axis and interpolar axis direct axis and interpolar axis quadrature axis and direct axis direct axis and indirect axis quadrature axis and interpolar axis direct axis and interpolar axis ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? None of these. To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. None of these. To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/120. PN/60. PN/3000. PN/2. PN/120. PN/60. PN/3000. PN/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor None of these. Remains same. Increase. Decrease. None of these. Remains same. Increase. Decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starter is not used with large DC motor for starting, it will damage the armature and commutator. provide execessive voltage drop in line. all of above. draw a starting current many times its rated full load current. damage the armature and commutator. provide execessive voltage drop in line. all of above. draw a starting current many times its rated full load current. ANSWER DOWNLOAD EXAMIANS APP
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