Electrical Machines The rotor of a three phase induction motor has an impedance of 0.4 + j4 ohm per phase at standstill the maximum torque occurs at a slip of _____________. 25 %. 15 %. 50 %. 10 %. 25 %. 15 %. 50 %. 10 %. 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% 40% 60% 38% 68% 40% 60% 38% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor of a 3 - Φ wound induction motor is provided with heavy copper or aluminium bars placed in rotor slots. heavy short-circuited end rings. three phase winding. single phase winding. heavy copper or aluminium bars placed in rotor slots. heavy short-circuited end rings. three phase winding. single phase winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. decreased. increased. remains same. kept constant to certain value. decreased. increased. remains same. kept constant to certain value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a motor falls from 1100 r.p.m at no-load to 1050 r.p.m at rated load. The speed regulation of motor is 2.56 %. 4.76%. 2.57 %. 3.76%. 2.56 %. 4.76%. 2.57 %. 3.76%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Capacitor start capacitor run provides high staring torque and high power factor. high staring torque only. high power factor only. none. high staring torque and high power factor. high staring torque only. high power factor only. none. ANSWER DOWNLOAD EXAMIANS APP