# Volume of water rainfall problem

what would the volume of water covering a 640 acre area be after 1 inch of rainfall?

## Answers and Replies

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rbj
theshark1019 said:
what would the volume of water covering a 640 acre area be after 1 inch of rainfall?
640 acre-inches?

DaveC426913
Gold Member
Surely it takes more time to write the post and wait for a response than to just figure it out on your own...

Or are you doing your homework during commercials?

You know, this isn't hard math, unless you're in second grade or something. Actually, second graders probably can do this now. Anyway, the answer is 1.57828283 × 10^-5 cubic miles.

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rbj
SkepticJ said:
You know, this isn't hard math, unless you're in second grade or something. Actually, second graders probably can do this now. Anyway, the answer is 1.57828283 × 10^-5 cubic miles.
spoon-feeder.:grumpy:

or, maybe, if it's numerically incorrect (i didn't check), spoon-feeding a wrong numerical answer is the best medicine.

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rbj said:
spoon-feeder.:grumpy:

or, maybe, if it's numerically incorrect (i didn't check), spoon-feeding a wrong numerical answer is the best medicine.
Sorry.

No, it's correct. I thought about giving him/her the wrong answer, but didn't. I've gone back and edited it to only leave the figure in cubic miles. That way I'm neither lying nor giving them an answer that won't raise an eyebrow with the teacher.

ETA, oh, blast, you've got my original post quoted, so my devious plan won't work.

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J77
SkepticJ said:
ETA, oh, blast, you've got my original post quoted, so my devious plan won't work.
They're hardly SI though

rcgldr
Homework Helper
Zero, it all soaked into the ground, or flowed away.

Chi Meson
Homework Helper
rbj said:
640 acre-inches?
You know, that's valid!
but convert acres into square meters and inches into meters first, then combine thiem to find cubic meters. (Divide that by 1000 to get liters).

J77 said:
They're hardly SI though
Well, acres and inches aren't SI, hectares and centimeters are. He/she said acres and inches in the OP.

theshark1019 said:
what would the volume of water covering a 640 acre area be after 1 inch of rainfall?
Hmm, now that would depend on the permeability of the soil.

Danger
Gold Member
Also upon the terrain. Unless it's walled in, the water won't be confined to the initial saturation area.

J77
SkepticJ said:
...hectares and centimeters are.
No they're not.

They can only be given, exactly in terms of an SI unit.

rcgldr
Homework Helper
SkepticJ said:
Well, acres and inches aren't SI, hectares and centimeters are. He/she said acres and inches in the OP.
Acre-feet is a common term for large amounts of water, usually behind a dam. So if 1 inch water fell into a 640 acre water tight basin, you'd have 53 1/3 (640/12) acre-feet, or 2323209.6 (53.3333... x 43560.18) ft^3 of water.

Bystander