Electrical Machines Cogging of induction motor occurs at low voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are not equal. high voltage and when stator and rotor poles are equal. low voltage and when stator and rotor poles are not equal. low voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are not equal. high voltage and when stator and rotor poles are equal. low voltage and when stator and rotor poles are not equal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T ∝ √P. T2 ∝ P3. T is independent of P. T ∝ P. T ∝ √P. T2 ∝ P3. T is independent of P. T ∝ P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The fall in speed of the DC generator due to increase in load can be corrected by increasing the input to the prime mover. cooling the armature. reducing the load voltage. increasing the excitation. increasing the input to the prime mover. cooling the armature. reducing the load voltage. increasing the excitation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The result of slip test on a 3-phase, 20 KVA, 400 V, 50 Hz connected salient pole alternator is given below- Phase value: Vmax = 100 V, Vmin = 96 V, Imax = 10 A and I min = 7 A. The direct and quadranature axis reactances are respectively 8.248 and 5.54 Ω. 8.248 and 9.60 Ω. 14.28 and 5.54 Ω. 14.28 and 9.60 Ω. 8.248 and 5.54 Ω. 8.248 and 9.60 Ω. 14.28 and 5.54 Ω. 14.28 and 9.60 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which DC motor will have least percentage increase of input current, for the same percentage increase in the torque Separately Excited DC Motor DC Shunt Motor DC Series Motor Compound Wound DC Motor Separately Excited DC Motor DC Shunt Motor DC Series Motor Compound Wound DC Motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of double squirrel cage winding on the rotor provides higher efficiency. a large starting torque. reduced starting torque. low noise. higher efficiency. a large starting torque. reduced starting torque. low noise. ANSWER DOWNLOAD EXAMIANS APP