Electrical Machines The brush-axis of a bipolar dc motor is rotated by 90°. The effect of this rotation on the back emf Eband the torque developed Tdwould be such that Eb is unchanged, but Td is zero both Eb and Td are unchanged both Eb and Td are zero Eb is zero, but Td is unchanged Eb is unchanged, but Td is zero both Eb and Td are unchanged both Eb and Td are zero Eb is zero, but Td is unchanged ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will continue to work as synchronous motor with same direction of rotation. start working as induction motor. come to stand still. continue to work as alternator but the direction of rotation will reverse. continue to work as synchronous motor with same direction of rotation. start working as induction motor. come to stand still. continue to work as alternator but the direction of rotation will reverse. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC Shunt Motor electromagnetic torque developed is Inversely proportional to the armature current. Proportional to the armature current. Proportional to the square of armature current. None of above. Inversely proportional to the armature current. Proportional to the armature current. Proportional to the square of armature current. None of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the rotating losses of machine? Hysteresis losses All of the them Eddy current losses Friction and windage losses Hysteresis losses All of the them Eddy current losses Friction and windage losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which is the arrangement of windings in a core type single phase transformer? Sandwiched lv and hv discs on each core limb Half hv inside and half lv outside on each core limb Lv on one core limb and hv on the other Half lv inside and half hv outside on each core limb Sandwiched lv and hv discs on each core limb Half hv inside and half lv outside on each core limb Lv on one core limb and hv on the other Half lv inside and half hv outside on each core limb ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by shifting the brush axis from GNA to MNA. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. increasing field excitation. shifting the brush axis from GNA to MNA. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. increasing field excitation. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS