Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is 115 V. 460 V. 230 V. 200 V. 115 V. 460 V. 230 V. 200 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous speed of an induction motor will be increased by increasing number of poles. speed can not be increased. increasing of frequency. decreasing of frequency. increasing number of poles. speed can not be increased. increasing of frequency. decreasing of frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + Ra. E = V + IaRa. E = V + Ia. E = V – IaRa. E = V + Ra. E = V + IaRa. E = V + Ia. E = V – IaRa. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 2, 3, 4, 5 1, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 2, 3, 4, 5 1, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, the demagnetizing effect of armature reaction is due to component of armature mmf along field axis magnetic saturation in half of the field pole non-sinusoidal nature of armature mmf uneven air-gap length component of armature mmf along field axis magnetic saturation in half of the field pole non-sinusoidal nature of armature mmf uneven air-gap length ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V DC machine has an armature resistance 1 Ω. If the full load current is 20 A, the difference of induced voltage between generator and motor is 20 V. 60 V. 0 V. 40 V. 20 V. 60 V. 0 V. 40 V. ANSWER DOWNLOAD EXAMIANS APP