Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. Back emf is equal to zero. None of above. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. Back emf is equal to zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5Ω and back back emf 200 V is 400 A. 44 A. 40 A. 440 A. 400 A. 44 A. 40 A. 440 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop DC motor torque. induction motor torque. induction generator torque. synchronous motor torque. DC motor torque. induction motor torque. induction generator torque. synchronous motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hunting in a synchronous cannot be due to variable frequency. variable supply voltage. variable load. windage friction. variable frequency. variable supply voltage. variable load. windage friction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Essential conditions for two DC generators are connecting for parallel operation is/are polarities should be same. terminal voltage should be same. both A and B. rating of generators should be same. polarities should be same. terminal voltage should be same. both A and B. rating of generators should be same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) ANSWER DOWNLOAD EXAMIANS APP
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