Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/120. PN/2. PN/3000. PN/60. PN/120. PN/2. PN/3000. PN/60. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an auto-transformer, power is transferred through induction process only. conduction process only. both A and B. None of these induction process only. conduction process only. both A and B. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines which of the following losses are negligible in blocked rotor test? iron loss copper loss mechanical loss both A and B iron loss copper loss mechanical loss both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2 A armature current at no-load, when the armature current is changed to 20 A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 1130 r.p.m. none of above. 4575.4 r.p.m. 1037.5 r.p.m. 1130 r.p.m. none of above. 4575.4 r.p.m. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For pure resistive load what is the armature reaction? All of these cross magnetization magnetization demagnetization All of these cross magnetization magnetization demagnetization ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP