(a) The speed at which the rotating magnetic field produced by stator currents rotates is (1)...

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(a) The speed at which the rotating magnetic field produced by stator currents rotates is (1) Synchronous speed (2) rotor speed (3) Greater than synchronous speed (b) A 3-phase, 400 V, 50 Hz, 4 pole induction motor runs at a slip of 5%. The relative speed between the rotor and stator magnetic fields is (1)1425 rpm (2) zero (3) 75 rpm (4) 1500 rpm (c) Rotating magnetic field due to rotor currents rotates relative to rotor surface at a speed equal to (1) sN. (2) N. (3) N (4) SN (d) The rotating field due to the rotor currents rotates relative to the stator core at a speed equal to (1) sN. (2) N. (3) N (4) SN (e) If the full load slip of a 3-phase induction motor operating at 50 Hz is 5%, the frequency of the rotor induced emf is (1) 2.5 Hz (2) 50 Hz (3) 5 Hz (d) 25 Hz (f) For a three phase, transposed overhead line, if you increase the phase spacing between adjacent conductors the resistance per phase will (1) increase (2) decrease (3) remain the same (4) cannot be predicted (g) If the diameter of a transmission line conductor is increased, then: (1) Both the inductance and capacitance increase (2) The inductance increases and the capacitance decreases (3) The inductance decreases and the capacitance increases (4) Both the inductance and the capacitance decrease (5) The inductance decrease and the capacitance remains unchanged the series reactance of the line by. (2) reduces, increasing (4)reduces, reducing (h) Bundling. GMR of the bundle. (1) increases, increasing (3) increases, reducing the (i) For three phase lines with unequal phase spacing, balance can be restored by completely transposing the line such that each phase occupies each position for of the line length. (1) half (3) two-third (2) one-third (4) either (1) or (2) (a) The speed at which the rotating magnetic field produced by stator currents rotates is (1) Synchronous speed (2) rotor speed (3) Greater than synchronous speed (b) A 3-phase, 400 V, 50 Hz, 4 pole induction motor runs at a slip of 5%. The relative speed between the rotor and stator magnetic fields is (1)1425 rpm (2) zero (3) 75 rpm (4) 1500 rpm (c) Rotating magnetic field due to rotor currents rotates relative to rotor surface at a speed equal to (1) sN. (2) N. (3) N (4) SN (d) The rotating field due to the rotor currents rotates relative to the stator core at a speed equal to (1) sN. (2) N. (3) N (4) SN (e) If the full load slip of a 3-phase induction motor operating at 50 Hz is 5%, the frequency of the rotor induced emf is (1) 2.5 Hz (2) 50 Hz (3) 5 Hz (d) 25 Hz (f) For a three phase, transposed overhead line, if you increase the phase spacing between adjacent conductors the resistance per phase will (1) increase (2) decrease (3) remain the same (4) cannot be predicted (g) If the diameter of a transmission line conductor is increased, then: (1) Both the inductance and capacitance increase (2) The inductance increases and the capacitance decreases (3) The inductance decreases and the capacitance increases (4) Both the inductance and the capacitance decrease (5) The inductance decrease and the capacitance remains unchanged the series reactance of the line by. (2) reduces, increasing (4)reduces, reducing (h) Bundling. GMR of the bundle. (1) increases, increasing (3) increases, reducing the (i) For three phase lines with unequal phase spacing, balance can be restored by completely transposing the line such that each phase occupies each position for of the line length. (1) half (3) two-third (2) one-third (4) either (1) or (2)

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a The speed at which the rotating magnetic field produced by stator currents rotates is Synchronous speed The synchronous speed of a motor is determined by the frequency of the power supply and the nu... View the full answer