Synchronous Motors A synchronous motor runs at speed ranging from ______ 150 to 1800 rpm 1800 to 3600 rpm 3600 to 6000 rpm None of the listed here 150 to 1800 rpm 1800 to 3600 rpm 3600 to 6000 rpm None of the listed here ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors By which of the following methods the constant speed of a synchronous motor can be changed to new fixed value ? By interchanging any two phases By changing the load By changing the supply frequency By changing the applied voltage By interchanging any two phases By changing the load By changing the supply frequency By changing the applied voltage ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors As the load is applied to a synchronous motor, the motor takes more armature current because The increased load has to take more current The back e.m.f. decreases causing an increase in motor current The rotor by shifting its phase backward causes motor to take more current The rotor strengthens the rotating field causing more motor current The increased load has to take more current The back e.m.f. decreases causing an increase in motor current The rotor by shifting its phase backward causes motor to take more current The rotor strengthens the rotating field causing more motor current 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 induced e.m.f. in a synchronous motor working on leading power factor will be less than the supply voltage equal to the supply voltage more than the supply voltage None of these less than the supply voltage equal to the supply voltage more than the supply voltage None of these ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Power factor of a synchronous motor is unity when The armature current is zero The armature current is maximum None of the listed here The armature current is minimum The armature current is zero The armature current is maximum None of the listed here The armature current is minimum ANSWER DOWNLOAD EXAMIANS APP