Electrical Machines The material used for commutator brushes is mostly copper. mica. carbon. cast iron. copper. mica. carbon. cast iron. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC series motor operating at rated speed, the speed of the motor will Reduce. Remain unaltered. Increase. Oscillate around the normal speed. Reduce. Remain unaltered. Increase. Oscillate around the normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor drawing an armature current of Ia is operating under saturated magnetic conditions. The torque developed in the motor is proportional to I/Ia2 Ia2 Ia 1/Ia I/Ia2 Ia2 Ia 1/Ia ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will increase to value lying between 220 V and 1.25 times 220 V not change and remain at 220 V increase to a value greater than 1.25 times 220 V increase to 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V not change and remain at 220 V increase to a value greater than 1.25 times 220 V increase to 1.25 times 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type of bearing is provided in small induction motors to support the rotor shaft? Cast iron bearings. Bush bearings. None of these Ball bearings. Cast iron bearings. Bush bearings. None of these Ball bearings. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to increase the permeability. reduce hysteresis loss only. reduce eddy current loss only. reduce both eddy current and hysteresis loss. increase the permeability. reduce hysteresis loss only. reduce eddy current loss only. reduce both eddy current and hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP