Synchronous Motors When the field of a synchronous motor is under-excited, the power factor will be unity zero leading lagging unity zero leading lagging ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors When a synchronous motor is pulled out of synchronism, the stator current ________ Become zero Is decreased too much Remains unchanged Is increased too much Become zero Is decreased too much Remains unchanged Is increased too much ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The back e.m.f. of a synchronous motor depends on load angle load All of these speed load angle load All of these speed ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors An important advantage of a synchronous motor over wound round induction motor is that None of these its power factor may be varied at will its speed is independent of supply frequency its speed may be controlled more easily None of these its power factor may be varied at will its speed is independent of supply frequency its speed may be controlled more easily ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors When load on an over-excited or under excited synchronous motor is increased, rate of change of its armature current as compared with that of power factor is equal twice less more equal twice less more ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The pull out torque of a synchronous motor is generally ______ times its full-load torque. 0.5 5 to 10 1.25 to 3.5 6 to 9 0.5 5 to 10 1.25 to 3.5 6 to 9 ANSWER DOWNLOAD EXAMIANS APP