Electrical Machines Saving of copper in auto transformer is increased as compared to two winding transformer, when transformation ratio K approaches to infinity. zero. unity. two. infinity. zero. unity. two. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power factor of an induction motor operating at no load will have a value around unity 0.9 lag 0.2 lead 0.2 lag unity 0.9 lag 0.2 lead 0.2 lag ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC machine having P no of pair of pole pairs, Z no of conductors having length L of resistivity ρ and cross section S are arranged. what is the armature resistance? PZL/4Sa² PZL/4S PZL/ 4Sa PZL/4Sp² PZL/4Sa² PZL/4S PZL/ 4Sa PZL/4Sp² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1, 2 and 4 1 and 3 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 2, 3 and 4 1, 2, and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For an ideal transformer the winding should have minimum resistance on primary side and maximum resistance on secondary side maximum resistance on primary side and least resistance on secondary side no ohmic resistance on either side equal resistance on primary and secondary side minimum resistance on primary side and maximum resistance on secondary side maximum resistance on primary side and least resistance on secondary side no ohmic resistance on either side equal resistance on primary and secondary side ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce hysteresis loss. to provide better flux linkage. to reduce mechanical losses. to reduce eddy current loss. to reduce hysteresis loss. to provide better flux linkage. to reduce mechanical losses. to reduce eddy current loss. ANSWER DOWNLOAD EXAMIANS APP
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