Question

If the distance between two point charges is doubled, the electrostatic force between them becomes—

• A. Double
• B. Half
• C. One-fourth
• D. Four times

Hint:

In Coulomb's law, if distance becomes: Double $\rightarrow$ Force becomes one-fourth Half $\rightarrow$ Force becomes four times

Answer 1

The Correct Option is C

According to Coulomb’s Law, the electrostatic force between two point charges is inversely proportional to the square of the distance between them.

Mathematically, Coulomb’s Law is expressed as:
F ∝ 1 / r²

If the original distance between the two charges is r and it is doubled (that is, made 2r), then the new force becomes:
F′ ∝ 1 / (2r)²
F′ ∝ 1 / 4r²

This means the new force is one-fourth (1/4) of the original force.

Therefore, if the distance between two point charges is doubled, the electrostatic force between them becomes one-fourth of its original value.