Electrical Machines The material used for commutator brushes is mostly mica. carbon. copper. cast iron. mica. carbon. copper. cast iron. 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. Rectangular hyperbola Straight line parallel to the speed axis. Circle about the origin. Straight line through the origin. Rectangular hyperbola Straight line parallel to the speed axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In shunt dc motor the direction of rotation of the motor will reversed. When none of above. either field terminals are reversed or armature terminals are reversed. only field terminals are changed. only armature terminals are reversed. none of above. either field terminals are reversed or armature terminals are reversed. only field terminals are changed. only armature terminals are reversed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V dc series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 Ω. The value of resistance which must be added to obtain rated torque at 1000 rpm is 2.2 Ω 1.9 Ω 5.7 Ω 6 Ω 2.2 Ω 1.9 Ω 5.7 Ω 6 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt motor has external resistance Ra and Rf in the armature and field circuits respectively. Armature current at starting can be reduced by keeping Ra maximum and Rf maximum Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf minimum Ra maximum and Rf maximum Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf minimum ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hysteresis loop represents the area of copper loss hysteresis loss total iron losses eddy current loss copper loss hysteresis loss total iron losses eddy current loss ANSWER DOWNLOAD EXAMIANS APP