Engineering Board Exam Reviewer · Voltage, Current and Resistance · medium
A copper wire has a resistance of 12, . A second wire of the same length and material has twice the diameter. What is its resistance?
- 3,
- 6,
- 24,
- 1.5,
Answer
A. 3,
Solution
Doubling the diameter multiplies the area by 4, so the resistance falls to 12/4=3, .
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