Electrical Machines In DC machine shape of main field flux distribution is? saddle shape flat tapped or trapezoidal peaky in nature triangular saddle shape flat tapped or trapezoidal peaky in nature triangular ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce hysteresis loss. to reduce mechanical losses. to reduce eddy current loss. to provide better flux linkage. to reduce hysteresis loss. to reduce mechanical losses. to reduce eddy current loss. to provide better flux linkage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 1, 4 1, 3 2, 3 2, 4 1, 4 1, 3 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then The magnetude of current will increase, but power factor will decrease. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnitude of current will decrease but the power factor will increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 5 1, 3, 5 1, 4, 6 1, 2, 6 1, 2, 5 1, 3, 5 1, 4, 6 1, 2, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Type of single phase motor having highest power factor at full load is capacitor start. shaded pole type. split phase. capacitor run. capacitor start. shaded pole type. split phase. capacitor run. ANSWER DOWNLOAD EXAMIANS APP