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 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 1, 2, 3 2, 3, 4 2, 3, 4, 5 2, 3 ,5 1, 2, 3 2, 3, 4 2, 3, 4, 5 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two mechanically coupled alternators deliver power at 50 Hz and 60 Hz respectively. The highest speed of the alternators is 3000 rpm. 500 rpm. 3600 rpm. 600 rpm. 3000 rpm. 500 rpm. 3600 rpm. 600 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the field winding connection must be reversed the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced the field winding connection must be reversed the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is used in grinders? Synchronous motor. Capacitor start capacitor run IM. Capacitor start IM. Split phase IM. Synchronous motor. Capacitor start capacitor run IM. Capacitor start IM. Split phase IM. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An unexcited single phase synchronous motor is AC series motor. universal motor. reluctance motor. repulsion motor. AC series motor. universal motor. reluctance motor. repulsion motor. ANSWER DOWNLOAD EXAMIANS APP
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