Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 25 W. 28 W. 36 W. 30 W. 25 W. 28 W. 36 W. 30 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in dc machine provide ----------------- rectification? half wave controlled half wave full wave controlled full wave half wave controlled half wave full wave controlled full wave ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC generator will not build up voltage if it has lost residual magnetism. due to wrong direction of rotation. any one of above. if field resistance is more than critical resistance. if it has lost residual magnetism. due to wrong direction of rotation. any one of above. if field resistance is more than critical resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because rotor winding is highly reactive. relative velocity between stator and rotor mmf’s is not zero. rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. rotor winding is highly reactive. relative velocity between stator and rotor mmf’s is not zero. rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a Circle about the origin. Straight line through the origin. Straight line parallel to the speed axis. Rectangular hyperbola Circle about the origin. Straight line through the origin. Straight line parallel to the speed axis. Rectangular hyperbola ANSWER DOWNLOAD EXAMIANS APP