Electrical Machines The speed regulation of a DC motor is given as NnL/NfL. NnL − NfL. (NnL − NfL)/NfL. (NfL − NnL)/NnL. NnL/NfL. NnL − NfL. (NnL − NfL)/NfL. (NfL − NnL)/NnL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Shunt Motor having shunt field resistance of 250 Ω and armature resistance of 0.5 Ω is connected to 250 V supply and load current of 21 A. What is the back emf generated ? 230 V. 210 V 240 V. 150 V. 230 V. 210 V 240 V. 150 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Brushes are always placed on--------------- , in order to achieve sparkles commutation? either GNA or MNA None of these GNA MNA either GNA or MNA None of these GNA MNA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The damper windings also called the squirrel cage windings or damper grids consists of short-circuited copper bars embedded in the field pole faces. are provided on the stator for improving power factor. are provided in a synchronous motor to make it self starting. both (A) and (B). consists of short-circuited copper bars embedded in the field pole faces. are provided on the stator for improving power factor. are provided in a synchronous motor to make it self starting. both (A) and (B). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator the actual flux distribution depends upon shape of the pole shoe. clearance between tips of the adjacent pole shoes. all of above. size of air gap. shape of the pole shoe. clearance between tips of the adjacent pole shoes. all of above. size of air gap. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. kept constant to certain value. remains same. decreased. increased. kept constant to certain value. remains same. decreased. increased. ANSWER DOWNLOAD EXAMIANS APP