Design & Sizing第 4 / 110 题
A fixture is located 46 ft above the water meter. Using 0.433 psi per foot of elevation, how much static pressure is lost to elevation between the meter and that fixture?
a.23.0 psi
b.34.5 psi
c.46.0 psi
d.19.9 psi
解析
Static loss = height x 0.433 psi/ft = 46 x 0.433 = 19.9 psi. Every foot of rise costs 0.433 psi and must be subtracted from the available supply pressure before you can check the residual at the fixture. The 46 psi answer wrongly treats 1 ft as 1 psi.
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