A wire of uniform area of cross section is cut into two parts of equal lengths. The resistivity of any part
Correct answer: A. Remain same
- A. Remain same
- B. Is doubled
- C. Is halved
- D. One fourth
Explanation
Resistivity is a fundamental property of a material, determined by its nature at the atomic level. It does not depend on the physical dimensions such as length or area of the wire. When a wire is cut into two equal lengths, only the resistance changes as it depends on the length and cross-sectional area. However, the resistivity remains the same for both parts because it is a characteristic of the material itself. Therefore, the correct answer is that the resistivity remains the same. The other options incorrectly suggest that resistivity is affected by the physical dimensions of the wire.
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Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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