First off i should say that right now Im working with gauss's law. The problem is finding the electric field between the different layers off 3 charged sheets. The top 2 are positive with 2 different charge densitys and the bottom one has a negative charge desity different from the top 2. The thing im haveing trouble with is Im not exactly sure how to calculate the feild between plates. Im not sure if i need to add the components from all 3 plates to get the field between the bottom and 2nd to top plate or if i should just use the components of force between the 2 bottom plates and forget about the component from the top plate. I would have though that the top plate would contribute to the field, and looking all through the chapter i cant find a similar cicum stance with 3 plates to help me out. I know i can pick my ouwn gaussian surfaces but it seems like if i did that so it only included the charges from 2 plates it would make my answer wrong since its not taking into effect the other plate so Im not sure what do do and would appreciate some help.