DC Motors A series motor will over speed when The load is increase The field is opened Load is removed The armature circuit is opened. The load is increase The field is opened Load is removed The armature circuit is opened. 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 A high value resistor is connected across the field winding A resistance is connected in series with armature Armature is temporarily open circuited A resistance is connected parallel to the armature A high value resistor is connected across the field winding A resistance is connected in series with armature Armature is temporarily open circuited A resistance is connected parallel to the armature ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which of the following motor is preferred for operation in highly explosive atmosphere? Shunt motor Series motor Air motor Battery operated motor Shunt motor Series motor Air motor Battery operated motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. motor is to be selected for conveyors, which rriotor would be preferred ? Shunt motor Differentially compound motor Series motor Cumulative compound motor Shunt motor Differentially compound motor Series motor Cumulative compound motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors In a dc machines the residual magnetism is of the order of 50 to 75 percent 20 to 25 percent 10 to 15 percent 2 to 3 percent 50 to 75 percent 20 to 25 percent 10 to 15 percent 2 to 3 percent ANSWER DOWNLOAD EXAMIANS APP
DC Motors In variable speed motor None of these A weaker commutating field is needed at low speed than at high speed Same commutating field is needed at low speed than at high speed A stronger commutating field is needed at low speed than at high speed None of these A weaker commutating field is needed at low speed than at high speed Same commutating field is needed at low speed than at high speed A stronger commutating field is needed at low speed than at high speed ANSWER DOWNLOAD EXAMIANS APP