Electrical Machines In a single phase transformer the magnitude of leakage reactance is twice that of resistance of both primary and secondary. With secondary short circuited, the input power factor is 2/√5 1/3 1/√2 1/√5 2/√5 1/3 1/√2 1/√5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the field excitation. varying the applied voltage. changing the load. varying the speed. changing the field excitation. varying the applied voltage. changing the load. varying the speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 5 KVA transformer has a turns ratio of N1/N2 = 10. The impedance of primary winding is 3+j5 ohms while that of secondary winding is 0.5+j0.8 ohms. The impedance of transformer when referred to primary will be 3.05+j5.08 ohms 53+j85 ohms 8+j13 ohms 3.5+j5.8 ohms 3.05+j5.08 ohms 53+j85 ohms 8+j13 ohms 3.5+j5.8 ohms ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Eg (generated emf) and Eb (back emf) both are same. changes. none of above. different. same. changes. none of above. different. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a cumulatively compound DC motor can be controlled by varying Armature voltage control. Shunt field resistance control. Armature resistance control. Any of above. Armature voltage control. Shunt field resistance control. Armature resistance control. Any of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motor cannot be started on no load? shunt motors both B and C cumulative compound motors series motors shunt motors both B and C cumulative compound motors series motors ANSWER DOWNLOAD EXAMIANS APP