12. Two conductor balls having charges 6 and 8 micro Coulomb are kept at a distance of 10 cm apart in free space. What is the force between them? Another conductor is touched with first and then, the second for sometimes and taken away. Now, find the new force experienced by the conductors. What is the nature of force? 13. Three charges of 1 C -1 C and 2 C are kept at the three vertices of the equilateral triangle ABC of side 10 cm. What would be the force at the charge kept at C? 14. In problem 13, what is the force at the charge kept at vertex A?