Electrical Machines In DC generators, the residual magnetism is of the order of 15 %. 20 %. 10 %. 2.5 %. 15 %. 20 %. 10 %. 2.5 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a dc motor the ratio Eb / E is indicative of ratio of starting to running torque. efficiency. ratio of starting to running current. ratio of input to output voltage. ratio of starting to running torque. efficiency. ratio of starting to running current. ratio of input to output voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of number of pole. Change of rotor resistance. Change of supply frequency. Change of supply voltage. Change of number of pole. Change of rotor resistance. Change of supply frequency. Change of supply voltage. 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% 68% 40% 60% 38% 68% 40% 60% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is increased, the power factor is None of these leading power factor lagging power factor unity power factor None of these leading power factor lagging power factor unity power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The frame of an induction motor is made of closed grained cast iron. stainless steel. silicon steel. aluminium. closed grained cast iron. stainless steel. silicon steel. aluminium. ANSWER DOWNLOAD EXAMIANS APP