Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at the speed of rotor in the air gap. rotates at slip speed with respect to stator mmf. is at standstill with respect to stator mmf. rotates at synchronous speed with respect to rotor. rotates at the speed of rotor in the air gap. rotates at slip speed with respect to stator mmf. is at standstill with respect to stator mmf. rotates at synchronous speed with respect to rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous motor is supplying a load at unity power factor. If the load on the motor is increased keeping its excitation and terminal voltage constant, the power factor None of these will become lagging will become leading will remain the same None of these will become lagging will become leading will remain the same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The change in speed of a DC generator due to increased load is corrected by increasing armature resistance. increasing armature cooling. increasing terminal voltage. increasing input power of the prime mover. increasing armature resistance. increasing armature cooling. increasing terminal voltage. increasing input power of the prime mover. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following, voltage regulation may be zero or negative All of these leading power factor unity power factor lagging power factor All of these leading power factor unity power factor lagging power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For small value armature current Ia the torque developed by a DC series motor is proportional to √Ia. 1/Ia. Ia2. Ia. √Ia. 1/Ia. Ia2. Ia. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines No load test of 3-phase induction motor gives which of the following? constant loss None of these variable loss both A and B constant loss None of these variable loss both A and B ANSWER DOWNLOAD EXAMIANS APP