Electrical Machines A 4 pole, 3-phase induction motor is running at 4% slip at full load. If the speed of the motor is 720 rpm, the supply frequency is 40 HZ 60 Hz 25 Hz 50 Hz 40 HZ 60 Hz 25 Hz 50 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the no-voltage release in a DC motor starter fails to operate on failure of supply, on resumption of supply the motor will get damaged. start automatically without trouble. not start automatically. develop very low starting torque. get damaged. start automatically without trouble. not start automatically. develop very low starting 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 225 Ω. 150 Ω. 145 Ω. 375 Ω. 225 Ω. 150 Ω. 145 Ω. 375 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a 3-phase, 4 pole, 50 Hz synchronous motor the frequency, pole number and the frequency are halved. The motor speed will be 3000 rpm 75 rpm 375 rpm 1500 rpm 3000 rpm 75 rpm 375 rpm 1500 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Cannot be predicted due to insufficient data. Would be equal to If1. Woud be equal to 2If1. Would be equal to If1/2. Cannot be predicted due to insufficient data. Would be equal to If1. Woud be equal to 2If1. Would be equal to If1/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following speed control of DC motor the speed obtained is below than the rated speed? Armature voltage control. Field resistance control. Armature circuit resistance control. Any of above. Armature voltage control. Field resistance control. Armature circuit resistance control. Any of above. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS