Two resistance wires of same material and same length have diameters in ratio 2:1. Their resistances are in ratio MCQ with Answer and Explanation

Two resistance wires of same material and same length have diameters in ratio 2:1. Their resistances are in ratio
A. 4:1
B. 2:1
C. 1:4
D. 1:2
Answer: Option C
Solution (By JKSSB Mock Tests)
R ∝ L/A ∝ 1/d². So R₁/R₂ = (d₂/d₁)² = (1/2)² = 1/4 = 1:4.

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