Electrical Machines A 2 pole synchronous machine is operating at 3000 rpm. Find the relation between electrical angular momentum (ωe) and mechanical angular momentum (ωm) ? ωe = 4*ωm ωe = 2*ωm ωe = ωm ωe = 1/2*ωm ωe = 4*ωm ωe = 2*ωm ωe = ωm ωe = 1/2*ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field system of an alternator is usually excited 3 - Φ, 50 Hz and 400 V. 250 / 250 V DC. 230 V AC. 110 / 220 V AC. 3 - Φ, 50 Hz and 400 V. 250 / 250 V DC. 230 V AC. 110 / 220 V AC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + IaRa. E = V + Ia. E = V + Ra. E = V – IaRa. E = V + IaRa. E = V + Ia. E = V + Ra. E = V – IaRa. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the magnetization characteristics of a dc generator : 1. It represents the variation of field flux with field current. 2. Variation of open-circuit terminal voltage with field current is independent of speed 3. It is non-linear from zero to rated field current 4. It helps to determine the critical field resistance at a given speed 5. It always starts from the origin Which of these statements are correct ? 1, 2 and 5 1 and 4 3 and 5 2, 3 and 4 1, 2 and 5 1 and 4 3 and 5 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the flux of DC motor approaches zero, its speed will approach zero. between zero and infinity. remain unchanged. aprroach infinity. approach zero. between zero and infinity. remain unchanged. aprroach infinity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Exciting current of an induction motor is higher than power transformer. lesser than power transformer. equal as power transformer. none of these. higher than power transformer. lesser than power transformer. equal as power transformer. none of these. ANSWER DOWNLOAD EXAMIANS APP