1. What is Coulomb's Law of Electric Force?

Definition: Coulomb's Law describes the electrostatic force between two charged particles. The force is proportional to the product of the charges and inversely proportional to the square of the distance between them.

Purpose: This calculator helps determine the magnitude of the electric force between two point charges.

2. How Does the Calculator Work?

The calculator uses the 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 their separation.

3. Importance of Electric Force Calculation

Details: Understanding electric forces is crucial in fields like electrical engineering, physics, and chemistry, helping design electrical systems and understand atomic interactions.

4. Using the Calculator

Tips: Enter both charges in Coulombs (1 electron = 1.602 × 10⁻¹⁹ C) and their separation distance in meters. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What if the charges have opposite signs?
A: The calculator gives magnitude only. Opposite charges attract (negative force), while like charges repel (positive force).

Q2: What's the value of Coulomb's constant?
A: \( k = 8.9875517923 \times 10^9 \) N m²/C² (often rounded to 8.99 × 10⁹).

Q3: Does this work for point charges only?
A: Yes, for non-point charges, integration over charge distributions is needed.

Q4: How does medium affect the force?
A: In other media, divide by the relative permittivity (εᵣ) of the medium.

Q5: What's the relationship with gravitational force?
A: Both follow inverse-square laws, but electric forces are much stronger.