First time taking physics in many years, so please forgive the simplistic nature of this problem. A 2.0 kg ball tied to a string fixed to the ceiling is pulled to one side by a force F. Just before the ball is released, (a) how large is the force F that is holding the ball in position and (b) what is the tension in the string? Also given: the angle between the string and the ceiling is 30 degrees. I understand everything up to the point that I've found the components of T and calculated: sum of x forces = Tcos30 (since in eqb sum of x forces=0) sum of y forces = Tsin30 (since in eqb sum of y forces =0) In the solutions manual, they are then taking F/w (force vector in positive-x direction/ weight vector in negative-y direction) = Tcos30/Tsin30 I don't understand why they are dividing F by w. I see that this will eliminate T so that you can solve for F, however, the decision to divide F by w seems arbitrary. Either that or I'm fundamentally missing something. Any insight?