Electrical Machines The magnetic field which initially induces emf in the armature in a self excited DC generator is because of residual magnetism. permanent magnets. armature reaction. None of these residual magnetism. permanent magnets. armature reaction. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At stand still condition the value of slip is 0 finite value 1 infinite value 0 finite value 1 infinite value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction depends on which of the following? power factor of load None of these both 1 and 2 magnitude of load current power factor of load None of these both 1 and 2 magnitude of load current ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The change in speed of a DC generator due to increased load is corrected by increasing input power of the prime mover. increasing armature cooling. increasing terminal voltage. increasing armature resistance. increasing input power of the prime mover. increasing armature cooling. increasing terminal voltage. increasing armature resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 2, 4 1, 4 1, 3 2, 3 2, 4 1, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 5 KVA transformer has a turns ratio of N1/N2 = 10. The impedance of primary winding is 3+j5 ohms while that of secondary winding is 0.5+j0.8 ohms. The impedance of transformer when referred to primary will be 3.05+j5.08 ohms 53+j85 ohms 3.5+j5.8 ohms 8+j13 ohms 3.05+j5.08 ohms 53+j85 ohms 3.5+j5.8 ohms 8+j13 ohms ANSWER DOWNLOAD EXAMIANS APP
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