Question

Derivation of the SI unit of Resistivity.

Answer 1

pls mark as brainliest for good explanation

pls here goes your answer;-

resistivity =Rl/A, right

now resistivity=Ωm/m²

Ω/m=Resistivity

pls

Answer 2

We know that,

Resistance is directly proportional to the Length

Also, Resistance is inversely proportional to the area of cross section

R ∝ l ----------(1)

R ∝ 1/A ----------(2)

From 1 & 2

R ∝ l/A

R = constant * l/A

Here, we take the constant as Rho such that ϱ = Resistivity

Since resistivity is a constant, it is independent of length and cross sectional area

$R \: = ϱ \frac{l}{A}$

Here, the unit of Resistance is Ω

Length = Metres

Area of cross section = Sq metres

$Ω = ϱ \frac{m}{ {m}^{2} }$

$Ω = \frac{ϱ} {m}$

or

$ϱ = \: Ωm$

Thus, the SI unit of Resistivity is ohm metre.