3/4" pipe is more than twice as big as 1/2" pipe!

Plumbing · Flow and Pressure · printed page 258 (PDF page 259)

Book index entries

Supply Plumbing – 3/4 Inch Pipe Flow and Pressure of Water in Supply Plumbing Supply Plumbing – Flow and Pressure Water Flow – and Pressure in Supply Plumbing

Text in the illustration

r=radius=0.25"
r
1/2"
diameter
1/2" pipe
cross sectional area
= pi x r²
= 3.14x(0.25)²
= 0.2 square inches
r=radius=0.375"
3/4"
3/4" pipe
= 3.14x(0.375)²
= 0.44 square inches

Generated explanation

The illustration compares circular cross sections of 1/2-inch and 3/4-inch water supply pipes. Gray rings represent the pipe walls, with arrows identifying the radius and diameter of each opening. The 1/2-inch pipe is labeled with a 0.25-inch radius and a calculated cross-sectional area of 0.2 square inches. The 3/4-inch pipe is labeled with a 0.375-inch radius and an area of 0.44 square inches. The comparison demonstrates that the larger pipe has more than twice the cross-sectional area of the smaller pipe.

Components

1/2-inch water supply pipe 3/4-inch water supply pipe pipe walls pipe openings