Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the field winding must be replaced the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding connection must be reversed the field winding must be replaced the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding connection must be reversed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to reduce magnetising current and improve power factor increase pull out torque improve starting torque decrease starting torque reduce magnetising current and improve power factor increase pull out torque improve starting torque decrease starting torque ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For higher values of armature, the speed of a DC series motor is Proportional to the square of armature current. Proportional to armature current. Inversely proportional to armature current. Constant. Proportional to the square of armature current. Proportional to armature current. Inversely proportional to armature current. Constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 6 pole lap connected DC generator with 480 conductors has armature resistance of 0.06 Ω. If the conductors are reconnected to from a wave winding other things remaining unchanged, the value of armature resistance will be 0.06 Ω. 0.54 Ω. 0.54 Ω. 0.01 Ω. 0.06 Ω. 0.54 Ω. 0.54 Ω. 0.01 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The commutator segments of DC machines are made up of hard-drawn copper copper alloy brass copper hard-drawn copper copper alloy brass copper ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The flux involved in the emf equation of a transformer has rms value. average value. maximum value. total value. rms value. average value. maximum value. total value. ANSWER DOWNLOAD EXAMIANS APP