Electrical Machines A DC cumulatively compounded motor delivers rated load torque at rated speed. If the series field is short-circuited, then the armature current and speed will both decrease decrease and increase respectively increase and decrease respectively both increase both decrease decrease and increase respectively increase and decrease respectively both increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the phase difference between two windings of A.C servomotor ? 120°. 90°. 30°. 60°. 120°. 90°. 30°. 60°. 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. open fuse or circuit breaker. develop excessive speed and damage itself. produce sparking at brushes. draw too much current. open fuse or circuit breaker. develop excessive speed and damage itself. produce sparking at brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 95% 96% 92% 94% 95% 96% 92% 94% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole dc generator is running at 1500 rpm the frequency of current in the armature winding is 100Hz. 150Hz. 50Hz. 200Hz. 100Hz. 150Hz. 50Hz. 200Hz. 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
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