Coulomb's Law Calculator
Calculate the electrostatic force between two point charges.
Step-by-step working
- F = k q₁ q₂ / r², k = 8987551792.3 N·m²/C²
- = 8987551792.3 × 3.0000e-6 × -2.0000e-6 / 0.1² = -5.3925 N
Mathematical Formula
Overview & Explanation
Like charges repel, unlike attract, with force ∝ 1/r².
How It Works
- Convert μC to C.
- Apply Coulomb’s law.
- Sign gives attraction or repulsion.
Practical Applications
- Electrostatics homework.
Example 1: +3 μC and −2 μC at 10 cm
Attractive ≈ 5.39 N.
Inputs
Charge q₁ (μC): 3 · Charge q₂ (μC): -2 · Distance (m): 0.1
Step 1
F = k q₁ q₂ / r², k = 8987551792.3 N·m²/C²
Step 2
= 8987551792.3 × 3.0000e-6 × -2.0000e-6 / 0.1² = -5.3925 N
Electrostatic force
Result
Example 2: two +1 μC at 1 m
≈ 9 mN.
Inputs
Charge q₁ (μC): 1 · Charge q₂ (μC): 1 · Distance (m): 1
Step 1
F = k q₁ q₂ / r², k = 8987551792.3 N·m²/C²
Step 2
= 8987551792.3 × 1.0000e-6 × 1.0000e-6 / 1² = 0.009 N
Electrostatic force
Result
How it's calculated & sources
F = k q₁ q₂ / r², k = 8.9875517923 × 10⁹ N·m²/C².
Frequently Asked Questions
What is k?
In a medium?
Point charges only?
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