Electrical Machines With the increase in speed of DC motor Back emf increase but line current falls. Back emf falls and line current increase. Both back emf as well as line current increase. Both back emf as well as line current fall. Back emf increase but line current falls. Back emf falls and line current increase. Both back emf as well as line current increase. Both back emf as well as line current fall. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for voltage build up in self excited generator? All of these Field winding should be properly connected to armature winding. Field winding resistance should be less than critical resistance. Poles should contain residual flux. All of these Field winding should be properly connected to armature winding. Field winding resistance should be less than critical resistance. Poles should contain residual flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The oscillation in a synchronous motor can be damped out by running the motor on leading power factors. maintaining constant excitation. oscillation cannot be damped. providing damper bars in the rotor pole faces. running the motor on leading power factors. maintaining constant excitation. oscillation cannot be damped. providing damper bars in the rotor pole faces. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A short circuit test on a transformer gives copper loss at over load. copper loss at half load. copper loss at full load. copper loss at any load. copper loss at over load. copper loss at half load. copper loss at full load. copper loss at any load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC shunt motors are suitable for Blowers and fans. All of this. Lathes. Centrifugal pumps Blowers and fans. All of this. Lathes. Centrifugal pumps ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω ANSWER DOWNLOAD EXAMIANS APP