1. The problem statement, all variables and given/known data Two small metallic spheres, each of mass 0.20 g, are suspended as pendulums by light strings from a common point as shown in the figure I attached. The spheres are given the same electric charge, and it is found that they come to equilibrium when each string is at an angle of 5.0 degrees with the vertical. If each string is 30.0 cm long, what is the magnitude of the charge on each sphere? 2. Relevant equations Coulomb's Law 3. The attempt at a solution I've drawn a force diagram for the first ball and I find that it's Fg=.00196, the tension, T, is .00197, and the Force of ball 2 on ball one, F21, is 1.71x10-4. When I plug into this equation: F=(ke|q|)/(r2), I get 5.1x10-9. However, I know this is wrong because the correct answer is 7.2nC. How do I do this correctly?