This is the question: A balloon rubbed against denim gains a charge of -8 x 10^ -6 C. What is the electric force between the balllon and denim when they are seperated by 0.05 m? That's all I know... I need to find the force between the two, all I know is the formula (Coulomb's Law), the distance, the constant (8.99 x 10^9), and that the balloon gains a negative charge. How do I figure it out? Is there a formula to calculate what the initial charges for the balloon and denim are?