Electrical Machines An induction motor has synchronous speed of 1500 rpm. What will be the slip when it is running at a speed of 1450 rpm? -3% +3.33% +3% -3.33% -3% +3.33% +3% -3.33% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be R2 = s2X2. sR2 = X2. R2 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. R2 = sX2. R2 = s2X2. 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 will remain the same None of these will become leading will become lagging will remain the same None of these will become leading will become lagging ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generator, brushes are always placed along armature axis. load axis. geometrical neutral axis. magnetic neutral axis. armature axis. load axis. geometrical neutral axis. magnetic neutral axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following motors DC excitation is not required? reluctance motor 3-phase synchronous motor 3-phase synchronous generator hysteresis motor reluctance motor 3-phase synchronous motor 3-phase synchronous generator hysteresis motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
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