DC Motors Excessive motor vibration is caused by Worn bearings Bent shaft Too much brush tension Open armature coil Worn bearings Bent shaft Too much brush tension Open armature coil ANSWER DOWNLOAD EXAMIANS APP
DC Motors As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit Armature is temporarily open circuited A resistance is connected in series with armature A high value resistor is connected across the field winding A resistance is connected parallel to the armature Armature is temporarily open circuited A resistance is connected in series with armature A high value resistor is connected across the field winding A resistance is connected parallel to the armature ANSWER DOWNLOAD EXAMIANS APP
DC Motors Usually wide and sensitive speed control is desired in case of Centrifugal pumps Colliery winders Steel rolling mills Elevators Centrifugal pumps Colliery winders Steel rolling mills Elevators ANSWER DOWNLOAD EXAMIANS APP
DC Motors The speed of a _____ motor is practically constant. Shunt Series Differentially compounded Cumulatively compounded Shunt Series Differentially compounded Cumulatively compounded 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 will remain constant Torque will change but power will remain constant Torque and power both will change Torque, power and speed, all will change Torque will remain constant Torque will change but power will remain constant Torque and power both will change ANSWER DOWNLOAD EXAMIANS APP
DC Motors During rheostat braking of dc series motor Motor is run at reduced speed None of the listed here Motor is run as a generator Motor is reversed in direction Motor is run at reduced speed None of the listed here Motor is run as a generator Motor is reversed in direction ANSWER DOWNLOAD EXAMIANS APP