Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.649. 0.512. 0.573. 0.443. 0.649. 0.512. 0.573. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 12 pole, 600 V, 50 Hz star connected IM has rotor resistance and stand still resistance of 0.03 Ω and 0.5 Ω respectively. The speed of maximum torque will be 450 rpm. 240 rpm. 470 rpm. 540 rpm. 450 rpm. 240 rpm. 470 rpm. 540 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The ventilating ducts in most of DC machine are radial. radial as well as longitudinal. none of these. longitudinal. radial. radial as well as longitudinal. none of these. longitudinal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing diverter resistance of a DC series motor causes decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed but armature currnet remains the same. increase in speed demanding more armature current. decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed but armature currnet remains the same. increase in speed demanding more armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of DC motor Both back emf as well as line current increase. Both back emf as well as line current fall. Back emf falls and line current increase. Back emf increase but line current falls. Both back emf as well as line current increase. Both back emf as well as line current fall. Back emf falls and line current increase. Back emf increase but line current falls. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For P pole machine relation between electrical degrees and mechanical degrees is θelec = 4/P*θmech θelec = P/2*θmech θelec = θmech θelec = 2/P*θmech θelec = 4/P*θmech θelec = P/2*θmech θelec = θmech θelec = 2/P*θmech ANSWER DOWNLOAD EXAMIANS APP