Coulomb's Law

Discussion

introduction

The force between two point charges is …

• directly proportional to the magnitude of each charge (q₁, q₂),
• inversely proportional to square of the separation between their centers (r),
• directed along the separation vector connecting their centers (r̂).

This relationship is known as Coulomb's Law. Charles Augustin de Coulomb (1736-1806) France. As an equation it is usually written in one of two forms …

text

• When two charges have the same sign
  their product is positive,
  which means the force vector is directed with the separation vector (r̂)
  and the action is repulsive.
• When two charges have the opposite sign
  their product is negative,
  which means the force vector is directed against the separation vector (r̂)
  and the action is attractive.

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