Question

3) A wire is 1m long, 0.2mm in diameter and has resistance of 10Ω. Calculate its resistivity.

Answer 1

$\huge\sf{Answer:}$

☆ Given:

⇒ A wire is 1m long, 0.2mm in diameter and has resistance of 10 Ω.

☆ Find:

⇒ Calculate it's resistivity.

☆ Know terms:

⇒ Length = (L)

⇒ Diameter = (D)

⇒ Resistance = (r)

⇒ Resistivity = (ρ)

☆ Note:

⇏ 1 m = 1000 mm

☆ We know that:

⇒ $\sf ρ = R \times \dfrac{A}{L}$

☆ Calculations:

⇒ $\sf A = π \times (0.1)^2$

⇒ $\sf A = 0.0314 \: mm^2$

⇒ $\sf ρ = 0.000314 \: Ω - mm$

⇒ ρ ≈ 3.14 × 10°⁻⁷ Ω m

Therefore, 3.14 × 10⁻⁷ Ω is the resistivity.

Answer 2

Hope it works................................™✌️✌️