1. What is Electric Force in Physics?

Definition: Electric force is the attractive or repulsive interaction between any two charged objects according to Coulomb's Law.

Purpose: This calculator helps determine the magnitude of force between two point charges, which is fundamental in electromagnetism and electrical engineering.

2. How Does the Calculator Work?

The calculator uses Coulomb's Law formula:

Where:

• \( F \) — Electric force (Newtons)
• \( k \) — Coulomb's constant (8.99 × 10⁹ N·m²/C²)
• \( q_1 \) — First charge (Coulombs)
• \( q_2 \) — Second charge (Coulombs)
• \( r \) — Distance between charges (meters)

Explanation: The force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.

3. Importance of Electric Force Calculation

Details: Understanding electric forces is crucial for designing electrical systems, analyzing atomic interactions, and explaining fundamental physical phenomena.

4. Using the Calculator

Tips: Enter the two charges in Coulombs (can be positive or negative), the distance between them in meters (must be > 0), and Coulomb's constant (default 8.99 × 10⁹ N·m²/C²).

5. Frequently Asked Questions (FAQ)

Q1: What does a negative force value mean?
A: Negative force indicates attraction between opposite charges, while positive indicates repulsion between like charges.

Q2: Why is distance squared in the formula?
A: The electric force follows an inverse-square law, meaning it weakens with the square of the distance.

Q3: What's a typical charge value?
A: Elementary charge is 1.6 × 10⁻¹⁹ C. Practical values range from nanocoulombs (10⁻⁹) to millicoulombs (10⁻³).

Q4: When would Coulomb's constant change?
A: The constant depends on the medium (8.99 × 10⁹ is for vacuum). For other materials, divide by the relative permittivity.

Q5: Does this work for point charges only?
A: The formula is exact for point charges and good approximation for spherical charges when r is much larger than their radii.