Solution:

Given that:

[tex]\tt\longrightarrow Length\:(l)=4m[/tex]

[tex]\tt\longrightarrow Area\:Of\:Cross\:Section\:(a)=0.1964\cdot 10^{-6}\:m^2[/tex]

[tex]\tt\longrightarrow Resistance\:(R)=10\:\Omega[/tex]

We know that resistivity is given by the formula:

[tex]\tt\longrightarrow Resistivity\:(\rho)=\dfrac{Resistance\:(R)\times Area\:(a)}{Length\:(l)}[/tex]

Substituting the values, we get:

[tex]\tt\longrightarrow \rho=\dfrac{10\:\Omega\times 0.1964\times 10^{-6}\:m^2}{4m}[/tex]

[tex]\tt\longrightarrow \rho=4.91\times 10^{-7}\:\Omega\:m[/tex]

Which is our required answer.

Answer:

[tex]\tt\hookrightarrow \rho=4.91\times 10^{-7}\:\Omega\:m[/tex]

Learn More:

Resistivity: The resistivity of a material is the resistance of a wire of that material of unit length and unit area of cross section.

Formula for resistivity:

[tex]\bigstar\:\:\underline{\boxed{\tt Resistivity\:(\rho)=\dfrac{Resistance\:(R)\times Area\:(a)}{Length\:(l)}}}[/tex]

SI Unit of resistivity: ohm x metre or Ωm.