Electrical Machines The speed regulation of a DC motor is given as NnL − NfL. (NfL − NnL)/NnL. NnL/NfL. (NnL − NfL)/NfL. NnL − NfL. (NfL − NnL)/NnL. NnL/NfL. (NnL − NfL)/NfL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes All of these They are not hard as copper brush They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes All of these They are not hard as copper brush ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 volt dc series motor having an armature resistance of 0.2 Ω takes a load current of 60 A. What will be the torque produced at the shaft of the motor? Consider brush drop of 1V. 234.76 N-m. 133.22 N-m can not be determined. 266.20 N-m. 234.76 N-m. 133.22 N-m can not be determined. 266.20 N-m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will increase to a value greater than 1.25 times 220 V not change and remain at 220 V increase to value lying between 220 V and 1.25 times 220 V increase to 1.25 times 220 V increase to a value greater than 1.25 times 220 V not change and remain at 220 V increase to value lying between 220 V and 1.25 times 220 V increase to 1.25 times 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines No load test on induction motor is conducted to find which of the following losses? Rotational loss All of these Stator copper loss Stator core loss Rotational loss All of these Stator copper loss Stator core loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor electromotive force of the IM is observed to make 100 complete alterations per minute, calculated slip 0 .001 %. 3 %. None of these 3.33 %. 0 .001 %. 3 %. None of these 3.33 %. ANSWER DOWNLOAD EXAMIANS APP