1. The problem statement, all variables and given/known data When an object is static (not moving), forces and moments must balance to zero. A moment here is defined as the force applied to an object multiplied by the distance from the point of rotation (torque). A simple way of thinking about moment balances is to consider a seesaw with a large child on one side and a small child on the other. The large child must sit loser to the fulcrum to balance the small child. Using force and moment, balances, find the magnitude FA, FB, and Fc in the following diagram (attached below). What is actually applying the force FB? 2. Relevant equations ΣFy = 0 ΣFx = 0 Σ T = 0 F = ma T = Fd 1lb = 4.45N 1in = 2.54cm 3. The attempt at a solution Well, first I converted all of my units from pounds to newtons and inches to meters. I assigned the variables wB for the weight of the ball and wA for the weight of the arm. wB = 10lbs = 44.5N wA = 3.5lbs = 15.58N ΣFy = 0 FBy - FA = -wB - wA FBy = FBsin(75) FBsin(75) - FA = -wB - wA ΣFy = 0 FC = -FBx Torque from arm weight = wAdA = (15.58N)(.183m) Torque from ball = wBdB = (44.5N)(.356m) Visually, these two torques can't possibly sum to zero, so I must be missing a torque... I know that the next step is to solve a system of equations, but I'm pretty sure these aren't the correct equations because I don't know how to draw a free body diagram for this complicated of a situation with all of the forces acting at different distances. I guess my questions are what forces am I missing? and when I draw the free body diagram, do I draw it as if all of the forces are acting at the same point?