Electrical Machines Short circuiting is caused in the armature winding due to failure of insulation between two turns of coil. any of above. grounding of two or more turns of the same coil. failure of insulation between two commutator bars. failure of insulation between two turns of coil. any of above. grounding of two or more turns of the same coil. failure of insulation between two commutator bars. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and the flux of a DC motor are held constant and voltage applied across its armature is increased by 5%, the speed of the motor will reduce by 5 %. increase by 5 %. depend on other factors. remain unchanged. reduce by 5 %. increase by 5 %. depend on other factors. remain unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 volt dc motor has an armature winding resistance of 0.5 ohm. Calculate the emf induced by the motor if the full load armature current is 23 ampere. None of these. 218.5 volt. 220.4 volt. 120 volt. None of these. 218.5 volt. 220.4 volt. 120 volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer operating at constant voltage if the input frequency increases, the core loss remains constant. increase. decrease. None of these remains constant. increase. decrease. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The constant losses in transformer is/are both 2 and 3. copper loss. eddy current loss. hysteresis loss. both 2 and 3. copper loss. eddy current loss. hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 2166.67V, 230 rpm. 541.67V, 250 rpm. 2166.67V, 270 rpm. 541.67V, 200 rpm. 2166.67V, 230 rpm. 541.67V, 250 rpm. 2166.67V, 270 rpm. 541.67V, 200 rpm. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS