Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 24.11 kW. 26.21 kW. 25 kW. 23.06 kW. 24.11 kW. 26.21 kW. 25 kW. 23.06 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the number of rotor slots is equal to number of stator slots, then motor refuses to start. Hence it is known as relative speed. cogging. air gap. crawling. relative speed. cogging. air gap. crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two single-phase alternators operating in parallel have induced EMFs on open circuit of 230∠0° and 230∠10° volts and respective reactance of j2 Ω j3 Ω calculate the terminal voltage 300 V. 150 V. 223.V. 200 V. 300 V. 150 V. 223.V. 200 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer cooling and insulating oil must be of low BDV. high viscosity. low resistivity. low viscosity. low BDV. high viscosity. low resistivity. low viscosity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Skewing of cage rotors offers the following advantages less noise. uniform torque. locking tendency is reduced. all of below. less noise. uniform torque. locking tendency is reduced. all of below. ANSWER DOWNLOAD EXAMIANS APP
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