Question Detail
Question
If the distance between the two point charges is doubled, the force between them decreases by?
Correct Answer
Option B is the correct answer.
Detailed Explanation
F is proportional to 1/r2. Doubling r reduces F to (1/2)2 = 1/4 of its original value - i.e. the force decreases (is divided) by a factor of four.
Hint
F is proportional to 1/r2.