Electrical Machines What is the necessity of copper brushes in a dc motors? To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. None of these. To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. None of these. To convert alternating supply current to direct current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum possible speed at which an alternator can be driven to generate 50 Hz and 4000 V is 1500 rpm. 4000 rpm. 3000 rpm. 3600 rpm. 1500 rpm. 4000 rpm. 3000 rpm. 3600 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The interpoles in dc machines have a tapering shape in order to reduce the overall weight reduce the saturation in the interpole economise on the material required for interpoles and their windings increase the acceleration of commutation reduce the overall weight reduce the saturation in the interpole economise on the material required for interpoles and their windings increase the acceleration of commutation ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two generators operating in parallel with rating 50MW and 100MW respectively. Both their respective governor settings are identical as 4%, consider same no load frequency. How will the machine share a common load of 100 MW 50 MW and 50 MW respectively 66.67 MW and 33.33 MW respectively 33.33 MW and 66.67 MW respectively any of the above 50 MW and 50 MW respectively 66.67 MW and 33.33 MW respectively 33.33 MW and 66.67 MW respectively any of the above ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A short-shunt cumulatively-compounded dc generator builds up a voltage of 220 V at no load at rated speed. If it is operated as a differentially compounded generator, other things remaining the same, it would build up somewhat less than 220 V 220 V 6 V more than 220 V somewhat less than 220 V 220 V 6 V more than 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Breather is provided in a transformer to absorb moisture of air during breathing. filter the transformer oil. absorb moisture from air entering in transformer. provide cold air in transformer. absorb moisture of air during breathing. filter the transformer oil. absorb moisture from air entering in transformer. provide cold air in transformer. ANSWER DOWNLOAD EXAMIANS APP
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