The study of forces on objects that do not move. Look at torque produced by the weight of a solid object. Determine the general conditions that must be satisfied for a system to be in static equilibrium. Perpendicular distance from pivot to center of mass is lever arm. Beam of mass m and length l with angle theta. The acceleration (all of them, angular and linear) are 0. Torque of hinge is 0, so you have torque of tension and weight equals zero. Torque of weight is just mg at the cm. Tension over the length times the vertical of the angle. Opposite directions so you can set them equal. Draw a picture that shows all forces and where the act. Apply newton"s 2nd law for translational and rotational motion. Choose a rotation axis that simplifies the calculation of the torques. Pick an axis, set hinge to zero (we don"t really need that information)