Why carbon brush used in dc motor also why its not used in ac motor?

2 Answers   RRB,

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how to calculate short circuit calculation of the transformer by usuing the percentage impedence? formula needed.

2 Answers   L&T,

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What is the slip speed?

0 Answers  

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What is AVR in Generators and How is it working.

4 Answers  

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If we are importing real power & exporting reactive power then what will be the effect on our system

3 Answers  

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If the load of transformer is getting more than its rating,,,than how to overcome this problem? Suppose thee rating of transformer is 315kva and the load is going beyond than the rating say around load: 352kva... Than how can we solve this problem without deducting the load.

14 Answers   Hyundai,

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What is the value of 3 phase voltage?

8 Answers   RECPDCL,

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why vacuume circuit breaker is not used for EHV

3 Answers   College School Exams Tests, Crompton Greaves,

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how to calculate the knee point voltage of current transformer?

2 Answers  

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why do power factor in the three phase induction motor increases with the load ???.

3 Answers   Jindal,

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Why we use duplex coil and hook switch in telephone system?

0 Answers  

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why induction generators are used in wind mills.why cant synchronous generators b used??

2 Answers  

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