When a wire of uniform cross-section a, length l and resistance R is bent into a complete circle, the resistance between any two diametrically opposite points will be
(1) R/4
Each semicircle has resistance R2.
Between diametrically opposite points the two halves are in parallel:
Req = (R/2)(R/2)R/2 + R/2 = R4
Answer: (1)
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