Coulomb’s Law Calculator
Coulomb law calculator
Compute electric force magnitude between two point charges.
Result
1.348132768845 N
Uses F = k|q1q2|/r^2 with k = 8.9875517923 × 10^9 N·m²/C².
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Advanced options
Flow
- Enter charge q1 and q2 in Coulombs.
- Enter separation distance r in meters.
- Review electrostatic force magnitude in Newtons.
Example
Worked example: q1=2e-6 C, q2=-3e-6 C, r=0.2 m
- 1 F = k|q1q2|/r^2
- 2 F = 8.9875517923e9 × |(2e-6)(-3e-6)| / 0.2^2
- 3 F ≈ 1.348 N
Electrostatic force magnitude is about 1.348 N.
How
- Enter charge q1 and q2 in Coulombs.
- Enter separation distance r in meters.
- Review electrostatic force magnitude in Newtons.
Avoid
- Entering microcoulombs without converting to Coulombs.
- Using distance in centimeters without meter conversion.
- Interpreting this magnitude-only output as directional vector result.
Checks
Best fit
Coulomb’s Law Calculator is built for compute electrostatic force magnitude between point charges using coulomb’s law. If Coulomb’s Law Calculator does not match the input scope, compare the answer with a second method.
Input check
Match the entered values to this rule before copying the answer: F = k × |q1q2| / r^2.
Sanity check
For Coulomb’s Law Calculator, use the worked example as a quick benchmark: Electrostatic force magnitude is about 1.348 N. If the coulomb’s law calculator answer is far away, check whether an input, unit, or mode changed.
Before copying
Review this common issue first: entering microcoulombs without converting to coulombs.
FAQ
Does sign of charge matter here?
Sign determines attraction/repulsion direction, while this tool reports magnitude.
Can I model dielectric media?
This version uses vacuum Coulomb constant by default.
Why must distance be non-zero?
Force scales with 1/r², so r = 0 is undefined.
Switch
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