Electrical Machines The core flux in transformer depends mainly on supply voltage and load supply voltage and frequency supply voltage, frequency and load supply voltage supply voltage and load supply voltage and frequency supply voltage, frequency and load supply voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To get the speed of DC motor is more than normal without wastage of electrical energy _____________ is used. Rheostatic control. Any of above method. None of above. Ward Leonard control. Rheostatic control. Any of above method. None of above. Ward Leonard control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 1, 2, 5 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 3, 4, 5 2, 3, 6 2, 4, 5, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Motor is driving a constant load torque having armature resistance of 0.25 Ω and armature current of 60 A having connected to a voltage of 230 V. Now a resistance of 1 ohm is added into the armature circuit. The ratio of their speed will be 0.72. 1.24. 0.62. 0.25. 0.72. 1.24. 0.62. 0.25. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer the magnetic coupling between the primary and secondary winding can be increased by using transformer oil of better quality. using soft material for winding. using the magnetic core of low reluctance. increasing the number of turns. using transformer oil of better quality. using soft material for winding. using the magnetic core of low reluctance. increasing the number of turns. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, for the same value of Æ, Z and N; which one of the following statements is correct? Armature emf is less with wave winding than with lap winding. Armature emf is more with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is less with wave winding than with lap winding. Armature emf is more with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is same as long as the flux density in the air gap remains the same. ANSWER DOWNLOAD EXAMIANS APP