1. What is Electric Field Strength?

Electric field strength (E) is a measure of the electric force per unit charge experienced by a small test charge placed in the field. It's a vector quantity with both magnitude and direction.

2. How Does the Calculator Work?

The calculator uses Coulomb's Law for electric fields:

Where:

• \( E \) — Electric field strength (N/C)
• \( k \) — Coulomb's constant (8.99×10⁹ N·m²/C²)
• \( Q \) — Source charge (C)
• \( r \) — Distance from the charge (m)

Explanation: The equation shows that electric field strength is directly proportional to the source charge and inversely proportional to the square of the distance from the charge.

3. Importance of Electric Field Calculation

Details: Calculating electric field strength is fundamental in electromagnetism, helping understand forces between charges, capacitor design, and electromagnetic wave propagation.

4. Using the Calculator

Tips: Enter charge in coulombs and distance in meters. The distance must be greater than zero. For point charges, this gives the field strength at that distance.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between electric field and electric force?
A: Electric field (E) is force per unit charge (N/C), while electric force (F) is the actual force experienced by a charge (F = qE).

Q2: Does the calculator work for negative charges?
A: Yes, though the result will be the magnitude. The direction would be toward a negative charge (opposite a positive charge).

Q3: What about multiple charges?
A: For multiple charges, calculate each field separately and vector sum them (this calculator handles single point charges only).

Q4: Why is distance squared in the formula?
A: This reflects the inverse-square law nature of electric fields, similar to gravity.

Q5: What are typical electric field strengths?
A: Near a 1μC charge at 1m: ~9000 N/C. Breakdown field strength in air is ~3×10⁶ N/C.