Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.649. 0.512. 0.443. 0.573. 0.649. 0.512. 0.443. 0.573. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC generator without commutator is a AC generator DC motor induction motor DC generator AC generator DC motor induction motor DC generator ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is 1, 2, 5 1, 2, 3, 4 1, 3, 5 2, 3, 4 1, 2, 5 1, 2, 3, 4 1, 3, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC shunt motor if load is increased, the speed increased slightly. increase proportional. remains constant. reduce slightly. increased slightly. increase proportional. remains constant. reduce slightly. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The principle of operation of a 3 - Φ induction motor is almost similar to that of synchronous motor. capacitor start induction motor. repulsion start induction motor. transformer with secondary short circuited. synchronous motor. capacitor start induction motor. repulsion start induction motor. transformer with secondary short circuited. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW? 48 Hz 50 Hz 45 HZ 48.5 Hz 48 Hz 50 Hz 45 HZ 48.5 Hz ANSWER DOWNLOAD EXAMIANS APP