Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4 2, 3, 4, 5 1, 2, 3 2, 3 ,5 2, 3, 4 2, 3, 4, 5 1, 2, 3 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Use of fractional pitch winding All of these results in reduced axial length of the machine. make it stiffer. results in reduced leakage reactance. All of these results in reduced axial length of the machine. make it stiffer. results in reduced leakage reactance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a single phase induction motor, the starting torque developed is proportional to 1/V² 1/V supply voltage V V² 1/V² 1/V supply voltage V V² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature shaft must be able to withstand bending moment due to weight of the armature. any unbalanced magnetic pull on the armature core. All of these twisting strains due to transmission of torque. bending moment due to weight of the armature. any unbalanced magnetic pull on the armature core. All of these twisting strains due to transmission of torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When two DC series motors are connected in parallel, the resultant speed is more than normal speed. zero. normal speed. less than normal speed. more than normal speed. zero. normal speed. less than normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In speed control of DC Series motor, speed lower than the rated speed can be obtained by Any of the above. Connecting an additional resistance in stator circuit. Connecting an additional resistance in the armature circuit. Connecting an additional resistance in the field circuit. Any of the above. Connecting an additional resistance in stator circuit. Connecting an additional resistance in the armature circuit. Connecting an additional resistance in the field circuit. ANSWER DOWNLOAD EXAMIANS APP