This problem is asking us to convert a volume in **inches times square kilometers** to **acre-feet**.

Whenever we convert units, the first step is to figure out what our starting and ending units are. We'll place the *starting units on the left*, an equals sign and *ending units on the right*, and some *conversion factors* in between.

Also, remember that if one of the starting units has an **exponent** (like **m**^{3} or **s**^{2}), the conversion factors for that unit __also__ need to have the ** same exponent**. For example:

$\left(\frac{{s}{t}{a}{r}{t}{i}{n}{g}{}{u}{n}{i}{t}}{{s}{t}{a}{r}{t}{i}{n}{g}{}{u}{n}{i}{{t}}^{{2}}}\right)\mathbf{\times}(conversionfactor)\mathbf{\times}{({c}{o}{n}{v}{e}{r}{s}{i}{o}{n}{}{f}{a}{c}{t}{o}{r})}^{\mathbf{2}}\mathbf{=}\left(\frac{{e}{n}{d}{i}{n}{g}{}{u}{n}{i}{t}}{{e}{n}{d}{i}{n}{g}{}{u}{n}{i}{{t}}^{{2}}}\right)$

The conversion factors *must* *cancel out* the starting unit and *leave* the ending unit. So to cancel out the **starting unit** in the ** numerator**, the first conversion factor must have that

The exact opposite happens with the **starting unit** in the ** denominator**. To cancel it, the second conversion factor must have that

Hydraulic engineers in the United States often use, as a unit of volume of water, the acre-foot, defined as the volume of water that will cover 1 acre of land to a depth of 1 ft. A severe thunderstorm dumped 2.0 in. of rain in 30 min on a town of area 26 km^{2}. What volume of water, in acre-feet, fell on the town?

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Unit Conversions concept. You can view video lessons to learn Unit Conversions. Or if you need more Unit Conversions practice, you can also practice Unit Conversions practice problems.

What is the difficulty of this problem?

Our tutors rated the difficulty of*Hydraulic engineers in the United States often use, as a uni...*as low difficulty.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Hatch's class at UMASS.

What textbook is this problem found in?

Our data indicates that this problem or a close variation was asked in Fundamentals of Physics - Halliday Calc 10th Edition. You can also practice Fundamentals of Physics - Halliday Calc 10th Edition practice problems.