Coulomb force
Coulomb force: use first charge, second charge, separation. Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
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Formula & explanation
F = k q₁q₂/r²; k≈8.9875517923×10⁹
Variables & units
- First charge
- C · minimum -1000000000000, maximum 1000000000000
- Second charge
- C · minimum -1000000000000, maximum 1000000000000
- Separation
- m · minimum 5e-324, maximum 1000000000000
Worked example
Use the displayed example inputs, then follow the substituted values in the solution.
Assumptions
Point charges in vacuum. Positive indicates like-charge repulsion; negative indicates attraction.
References
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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