Question

what is the best way to understand and breakdown free body diagrams!?

Answer 1

free body diagrams (fbd) are easy to figure out if you work out with the problem with a calm mind. First of all make a look at the system and then identify all the forces that are acting on it, then see that which of the force need to be broken into components acording to your co-ordinate system and then resolve the forces into the components along the axes of your co-ordinate system and then your fbd is ready.
assume the mass kept on the incline be represented by a point and let that point be the origin of the co-ordinate system.(here i have taken my cordinate system as follows:
x-axis=parallel to inclined surface and y-axis perpendicular to the inclined surface)
next, resolve the forces along the axes of yur co-ordinate system(i.e. break the forces on the body into its components)
next compute the total forces in all the directions by using newtons second law and then you can answer any question.
if you have any doubts , feel free to ask