DC Motors In variable speed motor 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 None of these ANSWER DOWNLOAD EXAMIANS APP
DC Motors The speed of a dc motor can be controlled by changing All of the listed here Aplied voltage Is flux Armature circuit resistance All of the listed here Aplied voltage Is flux Armature circuit resistance ANSWER DOWNLOAD EXAMIANS APP
DC Motors For starting a dc motor a starter is required because None of the listed here It limits the starting current to a safe value It starts the motor It limits the speed of the motor None of the listed here It limits the starting current to a safe value It starts the motor It limits the speed of the motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors The armature torque of the D.C. shunt motor is proportional to armature current only None of these both (A) and (B) field flux only armature current only None of these both (A) and (B) field flux only ANSWER DOWNLOAD EXAMIANS APP
DC Motors In case the conditions for maximum power for a D.C. motor are established, the efficiency of the motor will be Anywhere between 75% and 90% 1 Less than 50% Around 90% Anywhere between 75% and 90% 1 Less than 50% Around 90% ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which method of braking is generally used in elevators? Plugging Rheostat braking Regenerative braking None of these Plugging Rheostat braking Regenerative braking None of these ANSWER DOWNLOAD EXAMIANS APP
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