I have a problem (it was homework, but I already turned in my wrong answer) dealing with a block stationary on an accelerating inclined plane. There is a force applied horizontally to the inclined plane, which has an angle of 35 degrees above the horizontal. A box of mass 0.5 kg is on the plane, which has a mass of 2 kg. Coefficient of friction between the surfaces is 0.8. I need to find the maximum and minimum force on the plane to keep the block stationary. I've tried for several hours to solve this problem to no avail... I assume there are four forces on the block....gravity, normal force, friction force, and F' (which comes from the F on the wedge). I decided F' is 0.2 * F, since the block is 1/5th the total mass of the system. I thought the normal force was (m * g * sin(35)) + (F' * sin(angle)) .. but I doubt that's correct and it all goes downhill from there. Any help would be appreciated, thanks!