Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 50 Hz 0 Hz 25 Hz 100 Hz 50 Hz 0 Hz 25 Hz 100 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series generator is connected in series to a feeder having 0.5Ω resistance to boost the voltage. The induced voltage is given by Eg = 0.6Ia, Ra = 0.2Ω and Rs = 0.3Ω. Find the voltage boosted by the generator, when delivering 400 Amp? 30 V. 90 V. 60 V. 40 V. 30 V. 90 V. 60 V. 40 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then Pe will increase but Ph will decrease Ph will decrease but Pe will remain same Ph will increase but Pe will decrease both hysteresis loss(Ph) and eddy current loss(Pe) will increase Pe will increase but Ph will decrease Ph will decrease but Pe will remain same Ph will increase but Pe will decrease both hysteresis loss(Ph) and eddy current loss(Pe) will increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve efficiency. reduce copper loss. improve power factor. improve starting torque. improve efficiency. reduce copper loss. improve power factor. improve starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the handle of a three point starter goes to back to OFF position, it may be due to over load. zero or very low voltage supply. high filed circuit resistance. all of these. over load. zero or very low voltage supply. high filed circuit resistance. all of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to compensate for the decrease in speed due to increase of load. None of these neutralize voltage induced in coil due to fluctuation of l reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. None of these neutralize voltage induced in coil due to fluctuation of l reduce eddy current losses by providing local short circuits. ANSWER DOWNLOAD EXAMIANS APP
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