A copper wire of length 1 m and radius 1 mm is joined in series with a – McqOptions

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1.	A copper wire of length 1 m and radius 1 mm is joined in series with an iron wire of length 2 m and radius 3 mm and a current is passed through the wires. The ratio of the current density in the copper and iron wires is [MP PMT 1994]
A.	18 : 1
B.	9 : 1
C.	6 : 1
D.	2 : 3
Answer» C. 6 : 1

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