force exerted on an object by a plane

[kasheee]

Find the magnitude of the contact force exerted on P by the plane and the angle between the contact force and the upward direction of the line of greatest slope,
When a) P is in motion

b) P is at rest.


My question is this. Is the force exerted on P by the plane not the same regardless of whether or not it is motion (as the as the horizontal forces of the plane are independent of the vertical, i.e. the reaction force for example), and hence the angle should be the same in both cases? Thanks in advance.

 

[HallsofIvy]

Isn't there a picture or some more information for this problem? The answer will clearly depend upon the precise relative postions of the point and plane. Further "point" and "plane" are geometric concepts while "force" is a physical property. How is the plane going to apply any force at all to the plane? There must be some information you haven't mentioned.

 

[kasheee]

I am also stuck with how it is possible to be in position to answer this question. I wrote the question out word for word. No diagram came with the original question.

 

[Deleted member 4993]

.... Is the force exerted on P by the plane not the same regardless of whether or not it is motion ....

No ... the critical adjective to motion is "uniform" -

If the particle is in uniform motion (constant velocity), Newton's first law says the net force is equal to zero (same as the static case).

If the particle has acceleration (non-uniform motion) - then Newton's second law says .....