Which among the following equations give the correct relation between resistance(R), length of the conductor(L) and area of cross-section of the conductor(A)?
R=ρ×LA
The resistance of the conductor depends on,
(i) its length,
(ii) its area of cross-section, and
(iii) the nature of its material.
Measurements have shown that resistance of a uniform metallic conductor is directly proportional to its length (L) and inversely proportional to the area of cross-section (A).
R α L
R ∝ LA
⇒R=ρ × LA where ρ is the resistivity of the conductor.
Here, ρ is the constant of proportionality