Electrical Machines For a given torque, reducing divertor resistance of a DC series motor Increase in speed but armature currnet remains the same. Increase in speed demanding more armature current. Decrease in speed but armature current remains the same. Decrease in speed demanding less armature current. Increase in speed but armature currnet remains the same. Increase in speed demanding more armature current. Decrease in speed but armature current remains the same. Decrease in speed demanding less armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 920 RPM 970 RPM 960 RPM 940 RPM 920 RPM 970 RPM 960 RPM 940 RPM 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/3000. PN/2. PN/60. PN/120. PN/3000. PN/2. PN/60. ANSWER DOWNLOAD EXAMIANS APP
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? 10% 21% 11% 41% 10% 21% 11% 41% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The overall power factor of an on load transformer is always unity. is always lagging. is always leading. depends on the power factor of the load. is always unity. is always lagging. is always leading. depends on the power factor of the load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines _____________ types of induction motor are widely used. Squirrel cage IM. Slip ring IM. Three phase IM. Single phase IM. Squirrel cage IM. Slip ring IM. Three phase IM. Single phase IM. ANSWER DOWNLOAD EXAMIANS APP