Two charges of equal magnitude and at a distance ‘r’ exert a force F on each other. If the charges are halved and distance between them is doubled, then the new force acting on each charge is

Given data: a force F is applied between two charges of equal magnitude and separation r. Increasing the distance between them while halving the charges. 

Concept used: properties of electric charge

Detailed solution:

Force , F= $k\frac{{\left(\frac{q}{2}\right)}^2}{(2r{)}^2}=\frac{1}{16}F$