All the horziontal forces acting on a block are shown in the figure below. Vertical forces (support force and weight) cancel out. Determine the net horizontal force on the block. To determine the net horizontal force on the block, we need to consider the direction and magnitude of each force acting on it. From your description, it seems there are two forces acting in opposite directions: 1. A force of 15 N in one direction. 2. A force of 5 N in the opposite direction. 3. block= 20kg 15 N - 5 N = 10 N 5 N 15 N 15 N+ 5 N = 30 N