Electrical Machines A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle? 30° 20° 18° 60° 30° 20° 18° 60° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is 0.96 0.95 0.87 1.06 0.96 0.95 0.87 1.06 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a dc motor the ratio Eb / E is indicative of efficiency. ratio of starting to running current. ratio of input to output voltage. ratio of starting to running torque. efficiency. ratio of starting to running current. ratio of input to output voltage. ratio of starting to running torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A shunt generator has a critical field resistance of 300 Ω at a speed of 800 rpm if the speed is raised to 1000 rpm the critical field resistance is 150 Ω. 375 Ω. 225 Ω. 145 Ω. 150 Ω. 375 Ω. 225 Ω. 145 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 27.73 Nm . 74 Nm. 65.8 Nm. 38.5 Nm. 27.73 Nm . 74 Nm. 65.8 Nm. 38.5 Nm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines 1 KVA, 230 V, 50 Hz, single phase transformer has an eddy current loss of 30 watts. The eddy current loss when the transformer is excited by a dc source of same voltage will be 30 W more than 30 W less than 30 W zero watt 30 W more than 30 W less than 30 W zero watt ANSWER DOWNLOAD EXAMIANS APP