DC Motors Which one of the following is not the function of pole shoes in a D.C. machine? To spread out flux for better uniformity To reduce the reluctance of the magnetic path To support the field coils To reduce eddy current loss To spread out flux for better uniformity To reduce the reluctance of the magnetic path To support the field coils To reduce eddy current loss ANSWER DOWNLOAD EXAMIANS APP
DC Motors As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit A high value resistor is connected across the field winding A resistance is connected parallel to the armature Armature is temporarily open circuited A resistance is connected in series with armature A high value resistor is connected across the field winding A resistance is connected parallel to the armature Armature is temporarily open circuited A resistance is connected in series with armature ANSWER DOWNLOAD EXAMIANS APP
DC Motors In a dc motor constant torque is produced due to Commutator Rotor laminations Pole shoes End plates Commutator Rotor laminations Pole shoes End plates ANSWER DOWNLOAD EXAMIANS APP
DC Motors The mechanical power developed by a shunt motor will be maximum when the ratio of back emf to applied voltage is 2.0 0.5 4.0 1.0 2.0 0.5 4.0 1.0 ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which D.C. motor is generally preferred for cranes and hoists? Shunt motor Cumulatively compounded motor Series motor Differentially compounded motor Shunt motor Cumulatively compounded motor Series motor Differentially compounded motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 100% of the previous value 25% of the previous value 50% of the previous value 10% of the previous value 100% of the previous value 25% of the previous value 50% of the previous value 10% of the previous value ANSWER DOWNLOAD EXAMIANS APP
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