1. The problem statement, all variables and given/known data In the figure, two conducting balls of identical mass m = 20 g and identical charge q hang from nonconducting threads of length L = 100 cm. If x = 5.9 cm, what is q? Since x is much smaller than L approximate sin(θ) by θ. 2. Relevant equations Tcos theta = mg Tsin theta = ((kq^2)/x^2) (x/(2L) = (kq^2)/(mgx^2)) 3. The attempt at a solution Tcos theta = mg Tsin theta = ((kq^2)/x^2) Tan theta = sin theta/cos theta solve for tangent (x/(2L) = (kq^2)/(mgx^2)) then solve for q This is what a classmate of mine posted as a way to solve the problem, but it hasn't been working for me. Does this look like the right method? What does the T before cos and sin mean? Is it necessary to calculate theta, by sin(theta)=(0.059m/2)/(1 m) ....theta=1.69 deg ?