1. What is Resistivity?

Resistivity is the measure of how strongly a material opposes the flow of current through them. It is a fundamental property that characterizes the electrical conductivity of materials.

2. How Does the Calculator Work?

The calculator uses the resistivity formula:

Where:

• \( \rho \) — Resistivity (Ω·m)
• \( R \) — Resistance Overhead AC (Ω)
• \( A \) — Area of Overhead AC Wire (m²)
• \( L \) — Length of Overhead AC Wire (m)

Explanation: The formula calculates the resistivity of a material based on its resistance, cross-sectional area, and length.

3. Importance of Resistivity Calculation

Details: Accurate resistivity calculation is crucial for designing electrical systems, selecting appropriate materials for wiring, and ensuring efficient power transmission in overhead AC systems.

4. Using the Calculator

Tips: Enter resistance in ohms, area in square meters, and length in meters. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is the unit of resistivity?
A: Resistivity is measured in ohm-meter (Ω·m) in the SI system.

Q2: How does temperature affect resistivity?
A: For most conductors, resistivity increases with temperature. The relationship is typically linear over certain temperature ranges.

Q3: What are typical resistivity values for common materials?
A: Copper has resistivity of about 1.68×10⁻⁸ Ω·m, aluminum about 2.82×10⁻⁸ Ω·m, and silver about 1.59×10⁻⁸ Ω·m at room temperature.

Q4: Why is resistivity important in overhead power lines?
A: Resistivity determines the power loss in transmission lines. Lower resistivity materials reduce energy loss during power transmission.

Q5: How does resistivity differ from resistance?
A: Resistivity is an intrinsic property of the material, while resistance depends on both the material's resistivity and its dimensions (length and cross-sectional area).