Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 950 rpm 940 rpm 975 rpm 1000 rpm 950 rpm 940 rpm 975 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 100/10, 50 VA double winding transformer is converted to 100/110 V auto transformer. The rating of auto transformer is 110 VA 100 VA 500 VA 550 VA 110 VA 100 VA 500 VA 550 VA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage regulation of transformer is given by (E2 - V2) / V2 (E2 - V2) / E2 (V2 - E2) / E2 (V2 - E2) / V2 (E2 - V2) / V2 (E2 - V2) / E2 (V2 - E2) / E2 (V2 - E2) / V2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. remains unchanged. increased. decreased. kept constant to certain value. remains unchanged. increased. decreased. kept constant to certain value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a dc motor the ratio Eb / E is indicative of ratio of input to output voltage. efficiency. ratio of starting to running torque. ratio of starting to running current. ratio of input to output voltage. efficiency. ratio of starting to running torque. ratio of starting to running current. 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? 68% 60% 38% 40% 68% 60% 38% 40% ANSWER DOWNLOAD EXAMIANS APP