As shown in the figure, a body of mass(it is not a ball as in the figure) $m$ is placed on an inclined plane, and the plane is accelerating towards the right. It is also given that $a<g/\mu$.
Now the task is to find the angle at which the particle will be at rest w.r.t inclined plane.
The thing confusing me is which direction will be the force $ma$ acting on the body? Some force should be acting on the plane giving it acceleration $a$ then at the same time body will also get the force right?. But another possibility is as plane moves right body gets force of $ma$ towards left, how is that possible?
Another problem is if the body starts to move down the plane friction $f$ should be acting upwards and downwards otherwise. I tried to check the inequality $a<g/\mu$ as given in the question assuming body is moving downward but I couldn't deduce the inequality from it. How should we approach this problem?