Unit: Electricity and magnetism
Year: 1993 Question#: 30
Question: In the diagrams below, l represents a unit length of copper wire and A represents a unit cross-sectional area. Which copper wire has the smallest resistance at room temperature?
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(4
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What is this question really asking?
Explanation by: Dana H
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Answer 1
Incorrect having a small cross-sectional area creates resistance.
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Answer 2
Incorrect, the small cross-sectional area and long length creates the most resistance.
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Answer 3
Correct, A short length and a large cross-sectional area creates the least resistance.
Remember, short, fat, cold wires are the best conductors
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Answer 4
Incorrect, since the length is long, more resistance is created.
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What's this question really asking?
Which wire creates the least resistance?
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