Increasing the length of a wire, keeping other factors constant, its resistance
Answer and explanation
Correct answer: C. increases
Step 1. The electrical resistance of a uniform conductor is governed by the relation , where is electrical resistivity, is conductor length, and is cross-sectional area.
- Step 2: Because electrical resistance is directly proportional to length (), increasing the length of the wire while holding temperature, material, and cross-sectional area constant increases its resistance.
Answer
increases.
Why not the others: Resistance increases with length because electrons collide with more lattice ions; decreasing resistance requires shortening the wire or increasing thickness.
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