What happens to the force between two charges if the distance between them is tripled?

The force between two charges is governed by Coulomb’s law, which states that the force () between two charges is directly proportional to the product of the magnitudes of the charges (q1 and q2) and inversely proportional to the square of the distance () between them:

F=k.q1q2r/2

Where:

  • k is Coulomb’s constant.
  • r is the distance between the charges.

If the distance between the charges is tripled, the force will be affected by the square of the change in distance. Specifically, if the distance is tripled (r′=3r), the force will decrease by a factor of 32.

So, if the distance is tripled, the new force will be:

F′=F/9

This means that the force will be reduced to one-ninth of its original value.

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