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Electrical mathQuestion 830 of 1506

An aluminum busbar is 4 cm wide, 3 cm tall and 125 cm long. Its specific resistance is 2.65 × 10⁻⁶ Ω·cm. What is its end-to-end resistance along the 125 cm length?

  1. 3.31 × 10⁻⁴ Ω
  2. 2.76 × 10⁻⁵ Ω
  3. 2.54 × 10⁻⁷ Ω
  4. 1.77 × 10⁻⁹ Ω
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Correct answer: 2.76 × 10⁻⁵ Ω

Area = 4 × 3 = 12 cm². R = ρl/A = (2.65 × 10⁻⁶ × 125) / 12 = 2.76 × 10⁻⁵ Ω.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 12.5: Specific Resistance

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Questions last reviewed: 18 October 2026