R0=10Ω After stretching its length upto 2l R1=n2R0 =4R0 =40Ω 
RAB=20+2020×20=10Ω
A uniform metal wire of length / has 10Ω resistance. Now this wire is stretched to a length 2/ and then bent to form a perfect circle. The equivalent resistance across any arbitrary diameter of that circle is
Held on 30 Apr 2024 · Verified 9 Jul 2026.
10Ω
5Ω
40Ω
20Ω
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