DC Motors Excessive sparking at brushes may be caused due to Dirt on the commutator Worn bearings Loose coupling Misaligment of machine Dirt on the commutator Worn bearings Loose coupling Misaligment of machine ANSWER DOWNLOAD EXAMIANS APP
DC Motors The mechanical power developed by a shunt motor will be maximum when the ratio of back emf to applied voltage is 0.5 4.0 1.0 2.0 0.5 4.0 1.0 2.0 ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. motor designed for 40°C ambient temperature is to be used for 50°C ambient temperature, then the motor Of higher H.P. should be selected Of lower H.P. should be selected Can be used for 50°C ambient temperature also Is to be de-rated by a factor recommended by manufacturer and select the next higher H.P. motor Of higher H.P. should be selected Of lower H.P. should be selected Can be used for 50°C ambient temperature also Is to be de-rated by a factor recommended by manufacturer and select the next higher H.P. motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors A dc series motor is that which Has almost constant speed Can be started easily without load Has a poor torque Has its field winding consisting of thick wire and less turns Has almost constant speed Can be started easily without load Has a poor torque Has its field winding consisting of thick wire and less turns ANSWER DOWNLOAD EXAMIANS APP
DC Motors When the armature of a D.C. motor rotates, e.m.f. induced is None of these Mutually induced e.m.f. Back e.m.f. Self-induced e.m.f. None of these Mutually induced e.m.f. Back e.m.f. Self-induced e.m.f. ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. motor is to be selected for conveyors, which rriotor would be preferred ? Cumulative compound motor Series motor Differentially compound motor Shunt motor Cumulative compound motor Series motor Differentially compound motor Shunt motor ANSWER DOWNLOAD EXAMIANS APP