Electrical Machines A single-phase transformer has its maximum efficiency at 60 percent of full load. At full load copper loss will be zero. less than core loss. more than core loss. equal to core loss. zero. less than core loss. more than core loss. equal to core loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf of a DC machine has stepped distribution and rotates at the speed of armature. trapezoidal space distribution and is stationary in space. triangular space distribution and is stationary in space. triangular space distribution and rotates at the speed of armature. stepped distribution and rotates at the speed of armature. trapezoidal space distribution and is stationary in space. triangular space distribution and is stationary in space. triangular space distribution and rotates at the speed of armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to half the applied voltage. Back emf is equal to zero. Back emf is equal to applied voltage. None of above. Back emf is equal to half the applied voltage. Back emf is equal to zero. Back emf is equal to applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft of induction motor may be unbalanced due to uneven air gap. overheating of winding. overload. poor lubrication. uneven air gap. overheating of winding. overload. poor lubrication. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the commutator pitch? The distance between the staring of first coil and its next successive coil Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the front end of the armature. Number of conductors spanned by one coil at the back end of the armature. The distance between the staring of first coil and its next successive coil Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the front end of the armature. Number of conductors spanned by one coil at the back end of the armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The condition for maximum running torque is zero R = S.X 0.5 lagging 0.707 lagging unity zero R = S.X 0.5 lagging 0.707 lagging unity ANSWER DOWNLOAD EXAMIANS APP
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