DC Motors In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 10% of the previous value 25% of the previous value 50% of the previous value 100% of the previous value 10% of the previous value 25% of the previous value 50% of the previous value 100% of the previous value ANSWER DOWNLOAD EXAMIANS APP
DC Motors Excessive motor vibration is caused by Bent shaft Worn bearings Open armature coil Too much brush tension Bent shaft Worn bearings Open armature coil Too much brush tension ANSWER DOWNLOAD EXAMIANS APP
DC Motors In D.C. shunt motors as load is reduced The speed will increase in proportion to reduction in load The speed will reduce The speed will increase abruptly The speed will remain almost/constant The speed will increase in proportion to reduction in load The speed will reduce The speed will increase abruptly The speed will remain almost/constant 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 Armature is temporarily open circuited A resistance is connected parallel to the armature A resistance is connected in series with armature A high value resistor is connected across the field winding Armature is temporarily open circuited A resistance is connected parallel to the armature A resistance is connected in series with armature ANSWER DOWNLOAD EXAMIANS APP
DC Motors If the terminals of armature of D.C. motor are interchanged, this action will offer following kind of braking Plugging Dynamic braking None of these Regenerative Plugging Dynamic braking None of these Regenerative 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 Less than 50% Anywhere between 75% and 90% Around 90% 1 Less than 50% Anywhere between 75% and 90% Around 90% 1 ANSWER DOWNLOAD EXAMIANS APP
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