Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 100W 40W 60W 80W 100W 40W 60W 80W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor must started on no load because it would Run at dangerously high speed. Draw more current without producing sufficient torque. Fail to start without load. Not develop starting torque. Run at dangerously high speed. Draw more current without producing sufficient torque. Fail to start without load. Not develop starting torque. ANSWER DOWNLOAD EXAMIANS APP
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 20% increased by 10% increased by 20% reduced by 10% reduced by 20% increased by 10% increased by 20% reduced by 10% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be halved. It will becomes four times. It will be doubled. It will remain the same. It will be halved. It will becomes four times. It will be doubled. It will remain the same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Silicon content in steel lamination is kept within 5% as it increases hysteresis loss. makes the material brittle. Increases cost. All of these increases hysteresis loss. makes the material brittle. Increases cost. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutators in DC machines have a role of which converts Both AC to DC and DC to AC. AC to DC. none of these. high voltage DC to low voltage DC. Both AC to DC and DC to AC. AC to DC. none of these. high voltage DC to low voltage DC. ANSWER DOWNLOAD EXAMIANS APP