Electrical Machines If the load current and flux of a DC motor are held constant and voltage applied across it armature is increased by 5%, the speed of the motor will Depends on other factor. Reduce by 5%. Increase by 5%. Remain unchanged. Depends on other factor. Reduce by 5%. Increase by 5%. Remain unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field winding of a DC series motor is usually provided with thick wire as it carries large load current. to provide large flux. in order to reduce eddy current to provide large flux. to reduce the insulation of materials. as it carries large load current. to provide large flux. in order to reduce eddy current to provide large flux. to reduce the insulation of materials. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 stack stepper motor has 12 teeth on stator as well as on rotor. Determine the step size when each stack excited? 10°. 24°. 30°. 45°. 10°. 24°. 30°. 45°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 0.5 times the original value changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value changes to 1.5 times the original value remain the same as the original changes to three times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to reduce the chance of cogging. increase the starting torque. reduce the magnetizing current. reduce the chance of crawling. reduce the chance of cogging. increase the starting torque. reduce the magnetizing current. reduce the chance of crawling. 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. 14.28 and 5.54 Ω. 14.28 and 9.60 Ω. 8.248 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 5.54 Ω. 14.28 and 9.60 Ω. 8.248 and 9.60 Ω. ANSWER DOWNLOAD EXAMIANS APP