Example 1
Two charges of 1 µC separated by 1 m exert about 8.99 mN on each other.
Mendeleev
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Physics tools › Coulomb’s law
Mendeleev · Physics
Coulomb’s law
Two point charges exert an electrostatic force whose magnitude is proportional to both charges and decreases with the square of their separation.
Formula usedF = k|q₁q₂|/r²
Visual cue · field / circuit
Calculate
Coulomb’s law
What do the symbols mean?
Fforce
q₁charge 1
q₂charge 2
rradius
Two worked examples
Example 2
Halving the separation multiplies the force by four.
Good to knowThe calculator gives force magnitude for point charges in vacuum; the sign of the charges determines attraction or repulsion.