Electrical Machines Under commutation results in sparking at the leading edge of the brush. sparking the trailing edge of the brush. sparking at the middle of the brush. no sparking. sparking at the leading edge of the brush. sparking the trailing edge of the brush. sparking at the middle of the brush. no sparking. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Both rotor and stator winding. Rotor winding. Stator winding. Rotor mmf wave. Both rotor and stator winding. Rotor winding. Stator winding. Rotor mmf wave. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). None of these Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip rings of an induction motors are made of phosphor bronze. carbon. aluminium. stainless steel. phosphor bronze. carbon. aluminium. stainless steel. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When Flemings right hand rule to find the direction of induced emf, the thumb points towards direction of flux. opposite to the direction of motion of the conductor. direction of induced emf. direction of motion of the conductor. direction of flux. opposite to the direction of motion of the conductor. direction of induced emf. direction of motion of the conductor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3 ,5 2, 3, 4, 5 1, 2, 3 2, 3, 4 2, 3 ,5 2, 3, 4, 5 1, 2, 3 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP