Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to applied voltage. Back emf is equal to zero. Back emf is equal to half the applied voltage. None of above. Back emf is equal to applied voltage. Back emf is equal to zero. Back emf is equal to half the applied voltage. None of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machines have highest power factor with respect to magnetizing current? Semi closed slot type machine. Open slot type machines. Any of the above. Closed slot type machines. Semi closed slot type machine. Open slot type machines. Any of the above. Closed slot type machines. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following windings are necessary in case of all dc machines? open type winding wave winding lap winding closed winding open type winding wave winding lap winding closed winding ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC series motor operating at rated speed, the speed of the motor will Oscillate around the normal speed. Increase. Reduce. Remain unaltered. Oscillate around the normal speed. Increase. Reduce. Remain unaltered. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately-excited DC generator, running at rated speed, has 6 volts across its armature terminals with no field current. When field winding is excited with one ampere, the voltage builds up to 250 V at no load. In case field current is reduced to zero, with the speed remaining unaltered, the armature terminal voltage would be less than 6 V more than 6 V 6 V zero less than 6 V more than 6 V 6 V zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power factor of squirrel cage induction motor is low at light loads only both A and B low at rated load only low at heavy loads only low at light loads only both A and B low at rated load only low at heavy loads only ANSWER DOWNLOAD EXAMIANS APP