Many introductory books on electricity try to relate voltage to water pressure, electric current to water flow, and resistance to changes in pipe volume ... electrons drift through a conductor?

This way, engineers can figure out where the water needs to flow below ground in tunnels, on the surface in covered trenches or in pressurized pipes ... carve a tunnel through a mountain rather ...

that involves some sort of fluid such as water or air moving through pipes. If you don’t grasp hydraulics intuitively, [Practical Engineering] has a video you’ll enjoy. It explains how flow ...