Electrical Machines With the increase in speed of a DC motor both back emf as well as line current increase. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current fall. both back emf as well as line current increase. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current fall. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In electric locomotive which of the following motor are used ? Synchronous motor. Separately compound motor. Shunt motor. DC series motor. Synchronous motor. Separately compound motor. Shunt motor. DC series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power developed by salient pole synchronous machine is/are power due to saliency or reluctance only both 1 and 2 None of these excitation power only power due to saliency or reluctance only both 1 and 2 None of these excitation power only ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The supply voltage to an induction motor is reduced by 10%. By what percentage, approximately, will the maximum torque decrease? 5% 10% 19% 40% 5% 10% 19% 40% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by sf. f / s. s2. sf / 2. sf. f / s. s2. sf / 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : 1. interpole windings are connected in series with armature windings 2. polarity of interpoles must be the same as that of the main poles in advance 3. distortion of the main field under the pole shoes is not affected by the use of interpoles From above, the correct answer is 1 alone 1 and 3 2 and 3 1 and 2 1 alone 1 and 3 2 and 3 1 and 2 ANSWER DOWNLOAD EXAMIANS APP