Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the armature connection must be reversed the field winding must be replaced the field winding connection must be reversed field winding must be excited by low voltage dc supply the armature connection must be reversed the field winding must be replaced the field winding connection must be reversed field winding must be excited by low voltage dc supply ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc motors, under leading pole tips flux density will--------? increase None of these decrease either increase or decrease increase None of these decrease either increase or decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Oil is provided in an oil filled transformer for both cooling and insulation. lubrication. cooling. insulating. both cooling and insulation. lubrication. cooling. insulating. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a 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 Circle about the origin. Straight line through the origin. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + Ra. E = V + IaRa. E = V + Ia. E = V – IaRa. E = V + Ra. E = V + IaRa. E = V + Ia. E = V – IaRa. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the mechanical angle α between the stator and rotor poles increases, then the stator current None of above. Decreases. Remains unchanged. Increases. None of above. Decreases. Remains unchanged. Increases. ANSWER DOWNLOAD EXAMIANS APP
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