How much water does A pipe that is 4 inches by 2.5 feet tall hold?

Answer 1

Assuming you mean a 4 inch (internal) diameter circular pipe that is 2.5 ft. long, the volume is found by taking the cross-sectional area (pi times the square of the radius) times the length. 2.5 feet is 30 inches, and the radius of the pipe is 2 inches, so the volume in cubic inches is given by: 3.1416 * 2 * 2 * 30 = 376.99 cubic inches It's important to use consistent units throughout -- you don't want to use feet and inches, for example. We can also solve it in metric units, by converting everything to centimeters. We then get an answer in cubic centimeters (cc's, or milliliters). There are exactly 2.54 centimeters per inch, so the calculation is: 3.1416 * (2 * 2.54) * (2 * 2.54) * (30 * 2.54) = 6177.8 cc Since there are 1000 cc's in a liter, this can also be expressed as 6.1778 liters. Also, since we are only given the initial values accurate to a couple significant figures (and we're using an approximation of pi) , it's probably not worth reporting answers to five significant figures. Expressing the answer as 377 cubic inches or 6.18 liters is perhaps more appropriate. Of course, if the answer is desired in some other units (say, gallons), you'd need to apply the appropriate conversion. Converting our 6.18 liters to gallons, for example, results in an answer of about 1.63 gallons (there are 3.785 liters in a gallon). What if the pipe's *external* diameter is 4 inches, but the pipe walls are 1/4 inch thick? This would reduce the internal radius to 1.75 inches (4.445 cm), making the volume (pi * 1.75 * 1.75 * 30) = 288.6 cubic inches or 4.73 liters.