Here is the problem I have, it involves Newton's 2nd Law: A 12.0-kg block is pushed to the left across a rough horizontal surface by a force that is angled 30.0◦ below the horizontal. The magnitude of the force is 75.0 N and the acceleration of the block as it is pushed is 3.20 m/s^2 . What angle does the force exerted on the block by the surface make with the horizontal? I believe this is a Newton's 2nd law problem, but I have had trouble figuring out what the question is asking. I drew a free body diagram, where I have the normal force acting on the block perpendicular with the horizontal surface. In answering this question, is the angle simply the angle between the normal force and the horizontal? If i'm looking for the angle exerted on the block by the surface, is it just 90 degrees? Or is there more to solving this problem? Thanks for all the help.