Coulomb's Law Calculator
Calculate the electric force between two charged particles using Coulomb's Law.
Enter charges and distance to find the force.
Electric Force
Coulomb’s Law describes the electrostatic force between two point charges:
F = k × |q1 × q2| / r²
Where:
- F = force in Newtons (N)
- k = Coulomb’s constant = 8.9875 × 10⁹ N·m²/C²
- q1, q2 = charges in Coulombs (C)
- r = distance between charges in meters (m)
Key concepts:
- Like charges (both + or both -) → repulsive force
- Opposite charges (+ and -) → attractive force
- Force decreases with the square of the distance
- Doubling the distance reduces force to 1/4
Common charge magnitudes:
- Electron charge: 1.602 × 10⁻¹⁹ C
- Microcoulomb (μC): 10⁻⁶ C — typical static electricity
- Enter charges in microcoulombs (μC) for convenience