Explanation:
We begin by noting that there are two unknowns. Thus, we need two independent equations involving F1 and F2. For the first, we balance the horizontal components of forces acting on the member AB and write F1+F2 - 200 = 0. For the second, we balance the torque about point C and write 0.25 * 100 - 0.75 *100 + 1.5 * F1 = 0. From the latter equation, F1 = 33 1/3 N. From equation 1, F2= 166 2/3 N. You might wish to consider a more realistic model of the fencepost in which about 1/3 of the length of the post is buried in the earth. What is different about this latter situation from what is depicted in the figure?