Electrical Machines Which one of the following statement is correct ? In an induction motor if the air gap is increased then its speed will increase its speed will reduce its efficiency will improve its power factor will reduce its speed will increase its speed will reduce its efficiency will improve its power factor will reduce ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC motor is laminated to reduce the inductor. to reduce the mass. to reduce the eddy current loss. to reduce the hysteresis loss. to reduce the inductor. to reduce the mass. to reduce the eddy current loss. to reduce the hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field divertor resistance for a DC series motor is of order of 100 Ω 10 Ω 0.1 Ω 50 Ω 100 Ω 10 Ω 0.1 Ω 50 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2, 3 and 4 1, 2 and 3 3 only 1, 3 1, 2, 3 and 4 1, 2 and 3 3 only 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The principal of starting of 3 - Φ IM is similar to synchronous motor. repulsion motor type starting. transformer with short-circuited secondary. capacitor run IM. synchronous motor. repulsion motor type starting. transformer with short-circuited secondary. capacitor run IM. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.24 Ω. 0.66 Ω. 0.45 Ω. 0.78 Ω. 0.24 Ω. 0.66 Ω. 0.45 Ω. 0.78 Ω. ANSWER DOWNLOAD EXAMIANS APP