Arizona Plumbing Practice Exam

A 3 inch diameter pipe that is 20 feet long will contain how many cubic inches of water?

1. 1,695.6 cubic inches

2. 1,250.5 cubic inches

3. 1,980.3 cubic inches

4. 2,400.0 cubic inches

The correct answer is: 1,695.6 cubic inches

To determine the volume of a cylinder, which in this case is the pipe, you can use the formula for the volume of a cylinder: \[ V = \pi r^2 h \] Where: - \( V \) is the volume, - \( r \) is the radius of the cylinder, - \( h \) is the height (or length) of the cylinder. For the given problem: - The diameter of the pipe is 3 inches, so the radius is half of that, which is 1.5 inches. - The length of the pipe is 20 feet. Since we need to convert this measurement into inches (as there are 12 inches in a foot), the length in inches is \( 20 \times 12 = 240 \) inches. Now you can substitute these values into the formula: 1. Calculate the radius squared: \[ r^2 = (1.5)^2 = 2.25 \] 2. Then, substitute into the volume formula: \[ V = \pi \times 2.25 \times 240 \] 3. Approximating \( \pi \) as 3.1416, the calculation would be: \