Can anyone reccomend a website, or text, where there are step by step examples of setting up area and volume integrals where your looking for forces. I need to be able to do set ups for situations similar to the following :find the gravitational field vector on surface point of a cylinder or find or gravational force on a point mass from a disk. Really get confused with this-- especially when it comes to putting the pieces in terms of each other? Seems my calc. book just has me evalulate integrals and there's a big leap from my freshman/softmore physics text, where I hardly did any calc., to my junior level text. Thanks.