Electrical Machines In a star - delta starting of an IM reduced voltage is applied to the stator. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt resistance is inserted in the rotor. reduced voltage is applied to the stator. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt resistance is inserted in the rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop synchronous motor torque. induction motor torque. DC motor torque. induction generator torque. synchronous motor torque. induction motor torque. DC motor torque. induction generator torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory parallel operation of two transformers which of the following conditions is most essential, percentage impedance of all transformers must be same. polarities of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. voltage ratio of all transformers must be same. percentage impedance of all transformers must be same. polarities of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. voltage ratio of all transformers must be same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical load on it because otherwise it will draw too much current. develop excessive speed and damage itself. open fuse or circuit breaker. produce sparking at brushes. draw too much current. develop excessive speed and damage itself. open fuse or circuit breaker. produce sparking at brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous machine has P number of poles, find the relation between electrical angular momentum (ωe) and mechanical angular momentum (ωm)? ωe = P*ωm ωe = P/2*ωm ωe = 2/P*ωm ωe = ωm ωe = P*ωm ωe = P/2*ωm ωe = 2/P*ωm ωe = ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The slight curvature at the lower end of the OCC of a self excited DC generator is due to magnetic inertia. high speed. high field resistance. residual flux. magnetic inertia. high speed. high field resistance. residual flux. ANSWER DOWNLOAD EXAMIANS APP
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