Diameter of a pipe

I am trying to calculate the dia. of a pipe 60 inches long that will hold a gallon of water. What is the formula?

Landry

Hi Landry,

First you need to know which gallon. A US gallon is 231 cubic inches and a British imperial gallon is 277.42 cubic inches.

The volume of a cylinder is

r² L where r is the radius and L is the length. Your cylinder is 60 inches long so 60

r² = 231 or 60

r² = 277.42 Hence

if the gallons are US gallons or

if the gallons are British imperial gallons.

The diameter is twice the radius.

Cheers,
Penny Go to Math Central