A cylindrical wire AB consists of three equal parts AC, CD and DB, made of the same material but have different radii of cross-sections r, 3r and 5r. respectively. A battery is connected across the wire. Let v1, v2 and V3 be the potential differences across AC, CD and DB, respectively. Then :
1
V₁ ∶ V₂ ∶ V3 = 225 ∶ 25 ∶ 9
2
V₁ ∶ V₂ ∶ V3 = 1 ∶ 9 ∶ 25
3
V₁ = V₂ = V3
4
V₁ ∶ V₂ ∶ V3 = 1 ∶ 3 ∶ 5