# Work done by pumping water into a tank

1. Dec 17, 2011

### jdroidxw

1. The problem statement, all variables and given/known data

Problem with picture attached
I need help on 24. **24 is a continuation of 23 so use the same dimension except for the distance...

Or you can go here http://college.cengage.com/mathemat...alc8e_solution_main.html?CH=00&SECT=a&TYPE=se

Chapter 7, Lesson 5

2. Relevant equations

Volume=∏r^2*Δy
Water= 9800 N/m^3

∫(Volume)(water)(distance)=Work done ??

3. The attempt at a solution

Volume= 4∏Δy
Weight=9800*4∏Δy
Distance is where I'm not too sure about. Would I use (10-y)??
If so then I got...
∫9800*4∏Δy*(10-y), from 0 to 4 = 1,254,400∏ N-m

My answer looks really huge... Did I mess up anywhere?

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2. Dec 17, 2011

### I like Serena

Welcome to PF, jdroidxw!

You have the infinitesimal weight correct with 9800*4∏dy.

How far does the water that ends at the bottom have to be pumped up?
And how far does the water that ends at the highest level have to be pumped up?