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. 0.573. 0.649. 0.443. 0.512. 0.573. 0.649. 0.443. 0.512. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the e.m.f. generated by a 4 pole lap connected DC Generator rotating at 1500 r.p.m.? Its flux per pole is 0.4 mWb and total no of armature conductors is 1000. 30 volts. 20 volts. 40 volts. 10 volts. 30 volts. 20 volts. 40 volts. 10 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the increase in the torque expressed as percentage of initial torque, if current drawn by the dc series motor is increased from 10A to 11A? 10% 21% 41% 11% 10% 21% 41% 11% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause All of these vibrations. heating of rotor. double frequency currents in the rotor. All of these vibrations. heating of rotor. double frequency currents in the rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer which of the following losses are zero? Copper loss All of these Rotational loss Iron loss Copper loss All of these Rotational loss Iron loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type of motors uses slip rings? Both Synchronous and Induction motor DC Shunt Motor Synchronous motors Induction motors Both Synchronous and Induction motor DC Shunt Motor Synchronous motors Induction motors ANSWER DOWNLOAD EXAMIANS APP