Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be reduced by 10% reduced by 20% increased by 20% increased by 10% reduced by 10% reduced by 20% increased by 20% increased by 10% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called cogging. resonance. crawling. harmonics. cogging. resonance. crawling. harmonics. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The supply voltage to an induction motor is reduced by 10%. By what percentage, approximately, will the maximum torque decrease? 10% 40% 5% 19% 10% 40% 5% 19% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2 A armature current at no-load, when the armature current is changed to 20 A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 4575.4 r.p.m. none of above. 1130 r.p.m. 1037.5 r.p.m. 4575.4 r.p.m. none of above. 1130 r.p.m. 1037.5 r.p.m. 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 less than 30 W 30 W zero watt more than 30 W less than 30 W 30 W zero watt more than 30 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machine is invariably provided with forced ventilation? Fractional horse power slow speed motor. Hermetically sealed motor of refrigerator. 50 MW generator in a power plant. Fractional horse power high speed motor. Fractional horse power slow speed motor. Hermetically sealed motor of refrigerator. 50 MW generator in a power plant. Fractional horse power high speed motor. ANSWER DOWNLOAD EXAMIANS APP
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