Due to which of the following reasons, copper brushes in D.C. machine – McqOptions

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1.	Due to which of the following reasons, copper brushes in D.C. machine are used?
A.	when high voltage and small currents are involved
B.	when low voltage and high currents are involved
C.	in both of the above cases
D.	in none of the above cases
Answer» D. in none of the above cases

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