Electrical Machines An IM cannot run at synchronous speed because none of above. rotor torque will not be produced. air friction will prevent it. induction motor will become synchronous motor. none of above. rotor torque will not be produced. air friction will prevent it. induction motor will become synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running at rated speed without any additional resistance in series. If an additional resistance is placedin series, the speed of motor Increases. Decreases. Oscillates around the rated speed. Remains unchanged. Increases. Decreases. Oscillates around the rated speed. Remains unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field weakening control method is used for the _________ ? below rated speed None of these above rated speed both A and B below rated speed None of these above rated speed both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the mechanical power is developed by a DC motor maximum Back emf is equal. Back emf is equal to half of applied voltage. back emf is equal to applied voltage. None of above. Back emf is equal. Back emf is equal to half of applied voltage. back emf is equal to applied voltage. None of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor winding for a 3-phase slip-ring induction motor having delta-connected stator must be connected in star. None of these delta or star according to need. delta. star. None of these delta or star according to need. delta. 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 1, 4 2, 3 , 5 2, 4 ,5 1, 3, 5 1, 4 2, 3 , 5 ANSWER DOWNLOAD EXAMIANS APP