Electrical Machines The oscillation in a synchronous motor can be damped out by running the motor on leading power factors. providing damper bars in the rotor pole faces. oscillation cannot be damped. maintaining constant excitation. running the motor on leading power factors. providing damper bars in the rotor pole faces. oscillation cannot be damped. maintaining constant excitation. 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 more than 6 V zero less than 6 V 6 V more than 6 V zero less than 6 V 6 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The three point starter is used for Shunt motor as well as compound motors. Series motor. Shunt, compound and series motor. Shunt motor. Shunt motor as well as compound motors. Series motor. Shunt, compound and series motor. Shunt motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 2% 5% 25% 4% 2% 5% 25% 4% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft torque of a dc motor is less than the electromagnetic torque because of eddy current losses. ohmic losses. mechanical losses. hysteresis losses. eddy current losses. ohmic losses. mechanical losses. hysteresis losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Pi and Pc represent core and full load copper loss respectively, the maximum KVA delivered to load corresponding to maximum efficiency is equal to rated KVA is √(Pi/Pc) Pc/Pi Pi/Pc (Pi/Pc)2 √(Pi/Pc) Pc/Pi Pi/Pc (Pi/Pc)2 ANSWER DOWNLOAD EXAMIANS APP