Why the brushes used in dc machines are made of carbon not from other metal?

2 Answers  

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what is meant by vector group in transformers? wy we r using that?

1 Answers  

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how to calculate cable size, olr rating, contactor rating and mccb rating,to below given details three phase motor 75 kw,415 v,.85 pf,50 hz?

5 Answers   Cabin Crew, Essar,

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Which system is best for industries 3ph 3w or 3ph 4w?

3 Answers  

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what is ground fault current? is there any current flow takes place through ground? is it possible? if it's possible whether it affect human beings on earth near the fault or not?

2 Answers  

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415v 14kw so can u tell me how i can measure the cable size.then size of the earth also

1 Answers  

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How to do the meggering for a cable.

6 Answers  

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How to obtain B license from TNEB license board. What is eligibility?

11 Answers   Core, Reliance,

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If I have 3 essential main switch board and 3 incoming electricity ,but only 1 genset running is that possible.

0 Answers  

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model question paper for supervisor trainee

0 Answers   Bhel,

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what is the difference between STAR and DELTA connection and application wise how it can be utilizedd

0 Answers  

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Please define ohm’s law for a.c (alternating current)?

0 Answers  

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