1. What is Resistance Overhead AC?

Resistance Overhead AC is defined as the property of the wire or line that opposes the flow of current through it in an overhead AC transmission system.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The resistance of a conductor is directly proportional to its resistivity and length, and inversely proportional to its cross-sectional area.

3. Importance of Resistance Calculation

Details: Accurate resistance calculation is crucial for determining power losses, voltage drop, and efficiency in overhead AC transmission systems.

4. Using the Calculator

Tips: Enter resistivity in Ω·m, length in meters, and area in square meters. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What factors affect resistivity?
A: Resistivity depends on the material type and temperature. It increases with temperature for most conductors.

Q2: Why is resistance important in power transmission?
A: Higher resistance leads to greater power losses (I²R losses) and voltage drop in the transmission line.

Q3: How does wire area affect resistance?
A: Larger cross-sectional area reduces resistance, allowing more current to flow with less energy loss.

Q4: What are typical resistivity values for conductors?
A: Copper: 1.68×10⁻⁸ Ω·m, Aluminum: 2.82×10⁻⁸ Ω·m at 20°C.

Q5: Does AC resistance differ from DC resistance?
A: Yes, AC resistance is higher due to skin effect and proximity effect in alternating current systems.