DC Motors By putting controller resistance in series with the armature of a dc motor, we can obtain speeds Above the normal speed only Below the normal speed only None of the listed here Above as well as below the normal speed Above the normal speed only Below the normal speed only None of the listed here Above as well as below the normal speed ANSWER DOWNLOAD EXAMIANS APP
DC Motors In a dc machines the residual magnetism is of the order of 10 to 15 percent 2 to 3 percent 50 to 75 percent 20 to 25 percent 10 to 15 percent 2 to 3 percent 50 to 75 percent 20 to 25 percent ANSWER DOWNLOAD EXAMIANS APP
DC Motors Carbon brushes are preferable to copper brushes because _____ They have lower resistance They reduce sparking They reduce armature reaction They have longer life They have lower resistance They reduce sparking They reduce armature reaction They have longer life ANSWER DOWNLOAD EXAMIANS APP
DC Motors D.C. generators are normally designed for maximum efficiency around Full load All of these Rated voltage Rated r.p.m. Full load All of these Rated voltage Rated r.p.m. ANSWER DOWNLOAD EXAMIANS APP
DC Motors The shaft torque in a dc motor is less than total armature torque because of ______ in the motor. Cu losses None of the listed here Iron and friction losses Field losses Cu losses None of the listed here Iron and friction losses Field losses ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which of the following motor has the poorest speed regulation? Differentially compound motor Shunt motor Series motor Cummulative compound motor Differentially compound motor Shunt motor Series motor Cummulative compound motor ANSWER DOWNLOAD EXAMIANS APP