Electrical Machines For higher values of armature, the speed of a DC series motor is Constant. Inversely proportional to armature current. Proportional to armature current. Proportional to the square of armature current. Constant. Inversely proportional to armature current. Proportional to armature current. Proportional to the square of armature current. 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 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Winding conductors of an electrical power transformer are mainly insulated by wooden insulation. paper insulation. rubber insulation. cotton insulation. wooden insulation. paper insulation. rubber insulation. cotton insulation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. kept constant to certain value. increased. decreased. remains unchanged. kept constant to certain value. increased. decreased. remains unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 1, 4 2, 4 ,5 2, 3 , 5 1, 3, 5 1, 4 2, 4 ,5 2, 3 , 5 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a DC Shunt motor if the load is decreased to some extent, what will happen to its speed? The speed will remains almost constant. The speed will increase in proportion to reduction in load. The speed will increase abruptly. The speed will increase gradually. The speed will remains almost constant. The speed will increase in proportion to reduction in load. The speed will increase abruptly. The speed will increase gradually. ANSWER DOWNLOAD EXAMIANS APP