Coulomb's Law Calculator: Easily Calculate Electric Forces
Discover how to calculate electric forces using Coulomb's Law. Understand the underlying formula, review examples, and explore applications and limitations. To quickly determine the force between two charged particles, you can use our Coulomb-Law Calculator, which provides accurate results instantly and helps you apply Coulomb's Law in practical scenarios.
What is Coulomb's Law?
Coulomb's Law describes the electrostatic force between two charged objects. It explains that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
Coulomb's Law Formula
The formula for Coulomb's Law is expressed as:
F = k * (q1 * q2) / r²
Where:
- F: Electrostatic force (in Newtons, N)
- k: Coulomb's constant (8.99 × 10⁹ N·m²/C²)
- q1, q2: Charges of the particles (in Coulombs, C)
- r: Distance between charges (in meters, m)
Sample Calculations
Example 1: Two Like Charges
Consider two charges, q1 = 3 × 10⁻⁶ C and q2 = 5 × 10⁻⁶ C, separated by 0.02 meters:
F = (8.99 × 10⁹) * (3 × 10⁻⁶ * 5 × 10⁻⁶) / (0.02)²
= 33.71 N (repulsive force)
Example 2: Opposite Charges
For q1 = -4 × 10⁻⁶ C and q2 = 2 × 10⁻⁶ C, separated by 0.05 meters:
F = (8.99 × 10⁹) * (-4 × 10⁻⁶ * 2 × 10⁻⁶) / (0.05)²
= -28.76 N (attractive force)
Applications of Coulomb's Law
- Understanding atomic structure and electron interactions
- Explaining electric field behavior
- Designing capacitors and electric circuits
- Analyzing forces in electrostatic applications
Limitations of Coulomb's Law
- Applicable only to point charges or spherical distributions
- Ignores the medium’s effects between charges
- Doesn't account for quantum mechanical interactions
For practical applications, adjustments like dielectric constants may be needed.