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A copper wire of length 1 m and radius i...

A copper wire of length `1 m` and radius is joined in series with an iron wire of length `2 m` and radius `3 mm` and a current is passed through the wire. The ratio of the current density in the copper and iron wires is

A

`18 :1`

B

`9 :1`

C

`6:1`

D

`2 :3`

Text Solution

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The correct Answer is:
B
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ERRORLESS -CURRENT ELECTRICITY-Self Evaluation Test -19
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