DC Motors These days dc motors are widely used in Pumping sets Air compressors Electric traction Machine shops Pumping sets Air compressors Electric traction Machine shops ANSWER DOWNLOAD EXAMIANS APP
DC Motors For a D.C. shunt motor if the excitation is changed Torque, power and speed, all will change Torque and power both will change Torque will remain constant Torque will change but power will remain constant Torque, power and speed, all will change Torque and power both will change Torque will remain constant Torque will change but power will remain constant ANSWER DOWNLOAD EXAMIANS APP
DC Motors In a dc machines the residual magnetism is of the order of 10 to 15 percent 50 to 75 percent 2 to 3 percent 20 to 25 percent 10 to 15 percent 50 to 75 percent 2 to 3 percent 20 to 25 percent ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which of the following motor has the poorest speed regulation? Cummulative compound motor Shunt motor Differentially compound motor Series motor Cummulative compound motor Shunt motor Differentially compound motor Series motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors In case the conditions for maximum power for a D.C. motor are established, the efficiency of the motor will be 1 Around 90% Anywhere between 75% and 90% Less than 50% 1 Around 90% Anywhere between 75% and 90% Less than 50% ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens Nothing will happen to the motor This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses Motor will run at very slow speed This will make armature to take heavy current, possibly burning it Nothing will happen to the motor This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses Motor will run at very slow speed This will make armature to take heavy current, possibly burning it ANSWER DOWNLOAD EXAMIANS APP