Electrical Machines For a given torque, reducing divertor resistance of a DC series motor Increase in speed but armature currnet remains the same. Increase in speed demanding more armature current. Decrease in speed demanding less armature current. Decrease in speed but armature current remains the same. Increase in speed but armature currnet remains the same. Increase in speed demanding more armature current. Decrease in speed demanding less armature current. Decrease in speed but armature current remains the same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor power output of 3-phase induction motor is 15 KW. The rotor copper losses at a slip of 4% will be 600 W 650 W 625 W 700 W 600 W 650 W 625 W 700 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mechanical power is developed by a DC motor is maximum when back emf is equal to twice of applied voltage. none of above. back emf is equal to half of applied voltage. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. none of above. back emf is equal to half of applied voltage. back emf is equal to applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will shift forward by more than 90° shift forward by less than 90° coincide with the GNA shift forward by 90° shift forward by more than 90° shift forward by less than 90° coincide with the GNA shift forward by 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging in induction motor occurs when number of stator teeth - number of rotor teeth = even 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 = negative number. number of stator teeth - number of rotor teeth = even 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 = negative number. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 2, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
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