DC Motors The rheostatic speed control method is very Efficient Unsuitable for rapidly changing loads Economical Suitable for getting speeds above the normal Efficient Unsuitable for rapidly changing loads Economical Suitable for getting speeds above the normal ANSWER DOWNLOAD EXAMIANS APP
DC Motors The armature voltage control of dc motor provides Constant torque drive Constant voltage drive None of the listed here Constant current drive Constant torque drive Constant voltage drive None of the listed here Constant current drive ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which one of the following is not the function of pole shoes in a D.C. machine? To reduce the reluctance of the magnetic path To support the field coils To spread out flux for better uniformity To reduce eddy current loss To reduce the reluctance of the magnetic path To support the field coils To spread out flux for better uniformity To reduce eddy current loss ANSWER DOWNLOAD EXAMIANS APP
DC Motors If conditions for maximum power for a dc motor are established, the efficiency of the motor will be 80 to 90 % 100 % 60 to 70 % Less than 50% 80 to 90 % 100 % 60 to 70 % Less than 50% ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which of the following losses are significantly reduced by laminating the core of a D.C. generator? Windage losses Hysteresis losses Copper losses Eddy current losses Windage losses Hysteresis losses Copper losses Eddy current losses ANSWER DOWNLOAD EXAMIANS APP
DC Motors In variable speed motor None of these A stronger commutating field is needed at low speed than at high speed 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 None of these A stronger commutating field is needed at low speed than at high speed 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 ANSWER DOWNLOAD EXAMIANS APP