Hi @lap1, the force will be applied to the geometry in proportion to the surface area. So if all 15 faces are the same size you will have 2800 N applied to each face. If the faces are made up of different sizes the small faces will get less load and the large faces will get more load. The sum of all the loads on all the faces will equal the load defined in the force boundary condition (42000 N).
The applied force is not node density dependent, you can have a course or fine mesh and the load will still be applied according to surface area.
You can test this by applying a result control measure at the reaction(s). The reaction force should equal the applied load. You can also add result control measures to each load face to see how load is apportioned to each face.
Here is a simple example showing how to apply a load to multiple faces and check the reaction forces.
Use the post processor to check reaction forces.