Multiple Choice
A copper wire has a diameter of dCu = 0.0400 cm,is 3.00 m long,has a resistivity of 1.72 * 10-8 m and has a carrier density of 8.50 * 1028 electrons/m3.The copper wire is attached to an equal length of aluminum wire with a a carrier density of 6.02 * 1028 electrons/m3.A current of 0.400 A flows through the copper and aluminum wires.If the ratio of the current densities the two wires,JCu/JAl is 0.50,what is the diameter of the aluminum wire?
A) 0.0800 cm
B) 0.0283 cm
C) 0.0200 cm
D) 0.0565 cm
E) 0.0400 cm
Correct Answer:

Verified
Correct Answer:
Verified
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