A crate of mass M is placed on a frictionless inclined plane of Angle theta. Determine the acceleration after the crate is released. |\ |..\o crate of mass m |....\ |___b\ angle b which is theta. I know how to do this problem if I set up the axis a certain way. If I slant the axis so that the acceleration is in the X direction, then the problem is easy: F = MA F in the x direction = MGsin(theta) = MA in the x direction F in the y direction = N (normal force) -MGcos(theta) = 0 MA = MGsin(theta) A = Gsin(theta) However, I'm now asked to do the problem except with the axis the normal way, and while the free body diagram looks the same, I don't know how to precede from there because the axis are different. .../Normal force ../ .o object .| .| mg Here is the free body diagram.. F in the Y direction: Ncos(theta) - mg ?? something like this? F in the X direction: N sin(theta) F = ma Ncos(theta) - mg = MA in the y direction <- y component of acc. Nsin(theta) = MA in the X direction <- x component of acc. Something like that?