Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 9/16. 3/4. 4/3. 16/9. 9/16. 3/4. 4/3. 16/9. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging in induction motor occurs when number of stator teeth - number of rotor teeth = 0. number of stator teeth - number of rotor teeth = odd number. number of stator teeth - number of rotor teeth = even number. number of stator teeth - number of rotor teeth = negative number. number of stator teeth - number of rotor teeth = 0. number of stator teeth - number of rotor teeth = odd number. number of stator teeth - number of rotor teeth = even number. number of stator teeth - number of rotor teeth = negative number. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines There are two 2-pole DC machines. Main field axis of machine A is horizontal and that of B is vertical. It is preferable to purchase none of these machine B any of the two machines machine A none of these machine B any of the two machines machine A 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 1, 4 2, 3 2, 4 1, 3 1, 4 2, 3 2, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two transformers with identical rating, are designed with flux densities of 1.2 and 1.4 Wb / m2 respectively. The weight of first transformer per kVA is equal to that of second transformer. less than that of second transformer. more than that of second transformer. none of these. equal to that of second transformer. less than that of second transformer. more than that of second transformer. none of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft torque of a dc motor is less than the electromagnetic torque because of mechanical losses. eddy current losses. hysteresis losses. ohmic losses. mechanical losses. eddy current losses. hysteresis losses. ohmic losses. ANSWER DOWNLOAD EXAMIANS APP
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