Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Oscillate around the normal speed. Reduce. Increase. Remain unaltered. Oscillate around the normal speed. Reduce. Increase. Remain unaltered. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is 1.06 0.87 0.95 0.96 1.06 0.87 0.95 0.96 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The brushes of a DC machine should be placed on the armature in the polar axis. armature midway between poles. commutator in the polar axis. commutator in the inter polar axis. armature in the polar axis. armature midway between poles. commutator in the polar axis. commutator in the inter polar axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ wound rotor induction motor the short circuit gear is used to short circuit the stator phases of the motor. rotor at slip rings. starting resistance in the starter. None of these stator phases of the motor. rotor at slip rings. starting resistance in the starter. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer action requires a constant magnetic flux. alternating electric flux. increasing magnetic flux. alternating magnetic lux. constant magnetic flux. alternating electric flux. increasing magnetic flux. alternating magnetic lux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, if the supply voltage and frequency are reduced by the same ratio, then slip at which maximum torque occurs is less and maximum torque increases more and maximum torque decreases more and maximum torque remains constant less and maximum torque decreases less and maximum torque increases more and maximum torque decreases more and maximum torque remains constant less and maximum torque decreases ANSWER DOWNLOAD EXAMIANS APP
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