Assuming laminar viscous (meaning not frictionless) flow. Here is what I know about fluids flowing: You have a pressure difference between the two ends of the pipe. This causes a net force acting on the left side of the fluid in the pipe. Therefore, this incompressible fluid flows from left to right. Where it becomes abstract for me is following a section of this fluid as it travel along the pipe and what happens to it (A) I think it experiences a net force of 0 at all points because it is not accelerating. I am assuming the opposing force due to friction is keeping the net force at 0. (B) I am having trouble understanding why pressure gradually drops along the pipe or hose. The rightward pointing force acting on it is getting reduced. How exactly does this happen? If the fluid is incompressible, why isn't this section still feeling the same force as it did as the initial point in the hose?