# Net force on angled surface

#### rush02112

I prepared a drawing to reference what i am trying to explain:

http://i20.photobucket.com/albums/b225/rush02112/part1.jpg [Broken]

I will have pressure acting against the all surfaces of this part. Notice this part will only be able to move parallel to the center line of the part. I want to know if the net force acting against the 45 degree angle will be X in parallel direction of the centerline or if it is [cos(45)*X]

I was told by the engineer i work with that the angled surface will be pushed with force X parallel to the centerline. This is why i ask since that doesn't make sense to me. I would think that the force would act on the angled surface perpendicular to which the resulting force would be [(cos(45)*x]

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#### Dr.D

I prepared a drawing to reference what i am trying to explain:

http://i20.photobucket.com/albums/b225/rush02112/part1.jpg [Broken]

I will have pressure acting against the all surfaces of this part. Notice this part will only be able to move parallel to the center line of the part. I want to know if the net force acting against the 45 degree angle will be X in parallel direction of the centerline or if it is [cos(45)*X]

I was told by the engineer i work with that the angled surface will be pushed with force X parallel to the centerline. This is why i ask since that doesn't make sense to me. I would think that the force would act on the angled surface perpendicular to which the resulting force would be [(cos(45)*x]
If you really mean that you have a pressure acting on all of the surfaces, internal and external, then the net force will be zero and the part will be in equilibrium.

If you mean that you have pressure acting on the external surface only, then the net force is given by the "frontal area" or "projected area" multiplied by the pressure. This area is the area you see if you look at the part from the end.

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#### rush02112

Im just concerned about the 1 external angled surface at the moment. When this part is assembled in the tool, only a limited number of surfaces will see the force described. I wanted to try and keep the drawing and description as simple as possible

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