Question Detail
Question
Two point charges are 6 cm apart. They are moved to a new separation of 3 cm. By what factor does the resulting mutual force between them change?
Correct Answer
Option C is the correct answer.
Detailed Explanation
According to Coulomb's Law, the electrostatic force (F) between two point charges is inversely proportional to the square of the distance (r) between them (F ∝ 1/r²).Initial distance (r1) = 6 cm.New distance (r2) = 3 cm.r2 = r1 / 2.The ratio of the new force (F2) to the old force (F1) is:F2 / F1 = (1/r2²) / (1/r1²) = (r1/r2)²F2 / F1 = (6 cm / 3 cm)² = (2)² = 4.Thus, the force increases by a factor of 4.
Hint
Recall the inverse square relationship in Coulomb's Law.