1. The problem statement, all variables and given/known data Find the force necessary to start the crate moving, given that the mass of the crate is 32 and the coefficient of static friction between the crate and the floor is 0.58. The angle is 21 degrees below horizontal. 2. Relevant equations 3. The attempt at a solution I don't really understand where to go from here, I've found out the answer but really don't understand why we use the equations we do. Would appreciate any help regarding the logic behind the methods! My attempt: Weight = 32kg x 9.81 = 313.9 Newtons Normal Force = 313.9 cos(21) = 293 Newtons The force parallel to the plane = 313.9(sin21) = 112.5N The Force of Friction = 293 x .57 = 167N Now this is pretty much the farthest I can get without understanding what I'm doing. I think I did the above steps right I'm not completely sure. Would appreciate any help.