A wire has resistance 12 Ω. If it is bent into a circle and two points diametrically opposite are connected, the equivalent resistance between them is:
Correct answer: A. 3 Ω
- A. 3 Ω
- B. 6 Ω
- C. 9 Ω
- D. 12 Ω
Explanation
The wire is divided into two semicircular paths, each with resistance 12/2 = 6 Ω. These are in parallel between the diametric points, so Rₑ𝑞 = (6 × 6)/(6 + 6) = 36/12 = 3 Ω.
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