A wire of length l has resistivity π. If the wire Is divided in two halves, then resistivity of each halve is:
Correct answer: B. π
- A. π/2
- B. π
- C. 2π
- D. π/3
Explanation
When a wire is cut into two equal halves, the resistivity (π) of the material from which the wire is made remains unchanged. Resistivity is an intrinsic property that depends on the material itself and its temperature. Therefore, regardless of the length of the wire, each half retains the same resistivity as the original wire. Thus, the correct answer is π. Option A (π/2) is incorrect because resistivity does not decrease with the length of the wire. Option C (2π) mistakenly suggests that cutting the wire increases the resistivity, which is not the case. Option D (π/3) similarly misrepresents the concept, as resistivity remains constant for a given material.
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