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
F is proportional to 1/r2. Halving the distance (6cm -> 3cm) increases the force by a factor of 22 = 4.
Hint
F is proportional to 1/r2.