Resistance and Resistivity: The resistance of a 100-cm wire of cross sectional area 2 × 10-6 m2 is 400 ?. What is the resistivity of the material from which this wire is made?
A. 0.80 × 10-4 ? ? m
B. 8.0 × 10-4 ? ? m
C. 0.80 × 10-5 ? ? m
D. 0.80 × 10-6 ? ? m
E. 8.0 × 10-6 ?v
Answer: B
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