Electrical Machines In a transformer operating at constant voltage if the input frequency increases, the core loss remains constant. increase. None of these decrease. remains constant. increase. None of these decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field divertor method of speed control of a DC series motor gives speed above rated one due to reduction of None of above. Armature current. Line current. Field current. None of above. Armature current. Line current. Field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the magnetizing current. increase the starting torque. reduce the chance of crawling. reduce the chance of cogging. reduce the magnetizing current. increase the starting torque. reduce the chance of crawling. reduce the chance of cogging. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 38% 60% 40% 68% 38% 60% 40% 68% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Total core loss is also called as -------------? Eddy current loss Magnetic loss Copper loss Hysteresis loss Eddy current loss Magnetic loss Copper loss Hysteresis loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be 250 V. zero. about 100 V. very small, say about 2 or 3 V. 250 V. zero. about 100 V. very small, say about 2 or 3 V. ANSWER DOWNLOAD EXAMIANS APP