Electrical Machines As compared to an induction motor, the air gap in a DC motor is same. between 50% and 90%. less than 50%. more. same. between 50% and 90%. less than 50%. more. 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 1.25 times 220 V increase to a value greater than 1.25 times 220 V not change and remain at 220 V increase to value lying between 220 V and 1.25 times 220 V increase to 1.25 times 220 V increase to a value greater than 1.25 times 220 V not change and remain at 220 V increase to value lying between 220 V and 1.25 times 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a DC cummulative compound wound motor is loaded Both torque and speed decrease. Torque decrease and speed increases. Torque and speed both increase. Torque increase and speed decrease. Both torque and speed decrease. Torque decrease and speed increases. Torque and speed both increase. Torque increase and speed decrease. ANSWER DOWNLOAD EXAMIANS APP
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. 0.512. 0.443. 0.573. 0.649. 0.512. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A simple method of increasing the voltage of a DC generator is to increase the speed of shaft rotation. increase the number of turns in armature coil. increase the number of turns in field coil. increase the source frequency. increase the speed of shaft rotation. increase the number of turns in armature coil. increase the number of turns in field coil. increase the source frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature coil is short circuited by brushes when it lies along neutral axis. along field axis. in none of above positions. in any of above positions. along neutral axis. along field axis. in none of above positions. in any of above positions. ANSWER DOWNLOAD EXAMIANS APP