Final answer:
If the separation between two charges is changed to 1.16 times the initial distance, then the new electric force between them would be approximately 0.645 times the initial force.
Step-by-step explanation:
The electric force between two charges is given by Coulomb's law which states that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. If the separation between two charges is changed to 1.16 times the initial distance, then the new electric force between them would be (1/1.16)^2 times the initial force. In other words, the new force would be approximately 0.645 times the initial force.