Once we know these heads, we will then subtract the suction head from the discharge head and the amount remaining will be the amount of head that the pump must be able to generate at the rated flow. Here is how it looks in a formula: System head = total discharge head - total suction head. H = hd - hs.
Observation Point. This well used path climbs a short, steep, wooded hillside to a viewpoint of Old Faithful and nearby features, then continues across the hill to Solitary Geyser, a bubbling pool in an open area of the forest.
Letter charts are not only used to measure visual acuity, they are also used as targets for subjective refraction. This is the main reason distance acuity is measured more often than near acuity. At a long distance, accommodation is relaxed, so that the refraction can be more accurate.