1. The problem statement, all variables and given/known data Calculate the total charge embodied in a solid with charge density that decreases linearly with height from a value of λ at the bottom to 0 at the top. Solve for a rectangular prism and a sphere. 2. Relevant equations ∫∫∫ρdxdydz ∫∫∫pr^2sinθdrdθd∅ 3. The attempt at a solution For a rectangular prism, I integrated from 0 to x,y for dx,dy and lambda to 0 for dz. I ended up with Q=x*y*ρ*some function of λ. However, something seems off about this approach, because the charge at any x and y varies with height. I think if I can get the logic behind the prism, I'll be able to understand the sphere, but any other advice would be helpful.