Electrical Machines A 4 pole, 3-phase induction motor is running at 4% slip at full load. If the speed of the motor is 720 rpm, the supply frequency is 40 HZ 25 Hz 50 Hz 60 Hz 40 HZ 25 Hz 50 Hz 60 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions is a dc motor provided with compensating winding used ? 1. Wide range of speed control above normal 2. Wide range of steady load variation with no speed control 3.Wide range of rapid variation in load Select the correct answer using the codes given below : Codes : 1 and 3 2 and 3 1, 2 and 3 1 and 2 1 and 3 2 and 3 1, 2 and 3 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 6 pole lap connected DC generator with 480 conductors has armature resistance of 0.06 Ω. If the conductors are reconnected to from a wave winding other things remaining unchanged, the value of armature resistance will be 0.06 Ω. 0.54 Ω. 0.01 Ω. 0.54 Ω. 0.06 Ω. 0.54 Ω. 0.01 Ω. 0.54 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The slip of an induction motor during DC rheostatic braking is 2 + s. 1 - s. 2 - s. s. 2 + s. 1 - s. 2 - s. s. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. To absorb the mechanical shocks produced during running condition. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous generator, if mechanical input is increased with constant excitation, the load angle will None of these increase either increase or decrease decrease None of these increase either increase or decrease decrease ANSWER DOWNLOAD EXAMIANS APP