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How total number of brushes in a commutator are determined in a given DC machine?

How total number of brushes in a commutator are determined in a given DC machine? Correct Answer Amount of current to be collected

Brushes are in contact with rotating part and stationary part. Thus, if more amount of current is to be carried, it requires more number of brushes. Hence brush number depends directly on the amount of current that needs to be collected and fed up in or out.

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