Electrical Machines In a synchronous motor torque or load angle δ ------------- with increase in load decreases increases remains unaffected None of these decreases increases remains unaffected None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to three times the original value changes to 1.5 times the original value changes to 0.5 times the original value remain the same as the original changes to three times the original value changes to 1.5 times the original value changes to 0.5 times the original value remain the same as the original ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Air core transformer as compared to iron core transformer, has no magnetic core loss. more magnetic core loss. less magnetic core loss. more copper loss. no magnetic core loss. more magnetic core loss. less magnetic core loss. more copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The ___________________ generator has the poorest voltage regulation. differential compounded. shunt. under-compounded. over compounded. differential compounded. shunt. under-compounded. over compounded. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an induction motor, what is the ratio of rotor input to rotor copper loss? 1/(1-S) 1-S S 1/S 1/(1-S) 1-S S 1/S 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 : 1 and 3 2, 3 and 4 1, 2 and 4 1, 2, and 3 1 and 3 2, 3 and 4 1, 2 and 4 1, 2, and 3 ANSWER DOWNLOAD EXAMIANS APP