Electrical Machines If in DC Shunt Motor the flux is reduced suddenly to zero, then the motor will attain dangerously high speed. the speed of motor will be reduced. the armature current will reduce. the motor will come to stop. the motor will attain dangerously high speed. the speed of motor will be reduced. the armature current will reduce. the motor will come to stop. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a single phase induction motor driving a fan load, the reason for having a high resistance rotor is to achieve high efficiency. reduced size. low starting torque. quick acceleration. high efficiency. reduced size. low starting torque. quick acceleration. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If field current is decreased in shunt dc motor, the speed of the motor remains same. decreases. increases. None of these remains same. decreases. increases. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the chance of cogging. reduce the magnetizing current. increase the starting torque. reduce the chance of crawling. reduce the chance of cogging. reduce the magnetizing current. increase the starting torque. reduce the chance of crawling. 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%. 970 RPM 960 RPM 920 RPM 940 RPM 970 RPM 960 RPM 920 RPM 940 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of stator rotating magnetic field (RMF) with respect to rotor is Zero Nr S.Ns Ns Zero Nr S.Ns Ns ANSWER DOWNLOAD EXAMIANS APP