1. The problem statement, all variables and given/known data I fill a cylindrical tank of length 50 ft and diameter 90 ft with water (to the brim). What is the force the bottom 1 ft band of water exerts on the lining? 2. Relevant equations 3. The attempt at a solution My main doubt is whether i should integrate from 0 to 1 and add the weight of the water above or simply integrate from 49 to 50 and be done. Both yield significantly different results.