Electrical Machines If an induction machine is run at above the synchronous speed it acts as an induction generator None of these a synchronous motor an induction motor an induction generator None of these a synchronous motor an induction motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 500 V, 55 kVA single phase alternator has an effective resistance of 0.5 Ω. An excitation current of 10 A produces 200 A armature current on short circuit and an emf of 450 V on per circuit. The synchronous reactance will be 2.241 Ω. 2.781 Ω. 25.564 Ω. 2.74 Ω. 2.241 Ω. 2.781 Ω. 25.564 Ω. 2.74 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A bipolar dc machine with interpoles has a main-pole flux of ф per pole and an interpole flux of Фᵢ per pole. The yoke of the machine is devide into four quadrants by the main-pole axis and The commutation axis. The flux-distribution in the quadrants will be ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф - фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф - фᵢ ) in all the four quadrants ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flashing of DC generator means creation of residual magnetism by a DC source. increasing flux density by providing extra ampere-turns in field. neutralization of residual magnetism. None of these creation of residual magnetism by a DC source. increasing flux density by providing extra ampere-turns in field. neutralization of residual magnetism. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T2 ∝ P3. T is independent of P. T ∝ P. T ∝ √P. T2 ∝ P3. T is independent of P. T ∝ P. T ∝ √P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The brush-axis of a bipolar dc motor is rotated by 90°. The effect of this rotation on the back emf Eband the torque developed Tdwould be such that both Eb and Td are unchanged both Eb and Td are zero Eb is unchanged, but Td is zero Eb is zero, but Td is unchanged both Eb and Td are unchanged both Eb and Td are zero Eb is unchanged, but Td is zero Eb is zero, but Td is unchanged ANSWER DOWNLOAD EXAMIANS APP