Question Detail
Question
A length of wire has a resistance of 10 ohms. What is the resistance of a wire of the same material three times as long and twice the cross-sectional area?
Correct Answer
Option C is the correct answer.
Detailed Explanation
R = ρL/A. New R = ρ(3L)/(2A) = 1.5 × (ρL/A) = 1.5 × 10 = 15Ω
Hint
Resistance is proportional to length and inversely proportional to area.