Electrical Machines Transformer cooling and insulating oil must be of low BDV. low viscosity. low resistivity. high viscosity. low BDV. low viscosity. low resistivity. high viscosity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC generator beyond critical resistance will generate maximum current. maximum voltage. maximum power. no voltage. maximum current. maximum voltage. maximum power. no voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory parallel operation of two transformers which of the following conditions is most essential, voltage ratio of all transformers must be same. percentage impedance of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. polarities of all transformers must be same. voltage ratio of all transformers must be same. percentage impedance of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. polarities of all transformers must be same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A bipolar dc machine with interpoles has a main-pole flux of ф per pole and an interpole flux of Фᵢ per pole. The yoke of the machine is devide into four quadrants by the main-pole axis and The commutation axis. The flux-distribution in the quadrants will be ½ ( ф - фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ½ ( ф - фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 1, 3 1, 4 2, 4 2, 3 1, 3 1, 4 2, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to zero. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. None of above. Back emf is equal to zero. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. None of above. ANSWER DOWNLOAD EXAMIANS APP