Peoples Physics Concepts

9.3. Torque http://www.ck12.org

Solution

There will be multiple steps to this problem. First we’ll make a free body diagram for the rod; making free body

diagrams in torque problems is just as important as in Newton’s Laws problems. In the diagram, the force of

tension from the cable, the rod’s weight, and the forces from the hinge are shown. For the purposes of calculating

torque, an object’s weight acts from its center of mass (half way along the rod in this case). In the diagram below,

the force on the rod from the hinge is already broken into it’s components to make it easier to visualize.