Electrical Machines An ideal DC generated is one that has _____________ voltage regulation. positive. low. zero. negative. positive. low. zero. negative. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ 1/(φf) E ∝ f/φ E ∝ φ/f E ∝ φf E ∝ 1/(φf) E ∝ f/φ E ∝ φ/f E ∝ φf ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The inertia constant H of a synchronous condenser is greater than that of turbo alternator. none of these. greater than that of hydro generator. equal to that of the effective length of the line. greater than that of turbo alternator. none of these. greater than that of hydro generator. equal to that of the effective length of the line. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 2, 3 and 4 1, 2, and 3 1 and 3 1, 2 and 4 2, 3 and 4 1, 2, and 3 1 and 3 1, 2 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 94% 95% 92% 96% 94% 95% 92% 96% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 100 KVA transformer is operating at 60 Hz, 240 V supply. The same transformer is operating at 50 Hz, 200 V supply. The new rating is 50 KVA 100 KVA 123.3 KVA 83.33 KVA 50 KVA 100 KVA 123.3 KVA 83.33 KVA ANSWER DOWNLOAD EXAMIANS APP