# Homework Help: Finding volume by using cross section?

1. May 26, 2012

### exibo177

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

The only given data is that the cross section is 1m^2, the shape is circular (like a cut wire/rod) and i have to find the volume.

2. Relevant equations

from what i've searched, i found the equation:

but i have no idea what to do with it, i still haven't learned it at school.
if you know any other way to do it, please tell me with explanations. thank you!

3. The attempt at a solution

2. May 26, 2012

### Encephalon

If you have the cross section of a cylinder, then you can find the radius
$A=\pi r^2 => r=\sqrt{A/\pi}$
From the radius, you could find the volume if you were dealing with a sphere, or if you are dealing with a cylinder, you would need a length/height.
$V_{cylinder} = \pi r^2 l \\ V_{sphere} = 4/3 \pi r^3$

3. May 26, 2012

### exibo177

So my A here is 1m^2?

4. May 26, 2012

### truesearch

To find the volume of a rod of uniform crossection area (square, circular, triangular....it does not matter) the equationis L x area
so if area is 1m^2 and the rod is 1 m long the volume is 1m^3, 10m long it is 10m^3 and so on

5. May 26, 2012

### World

edit, misposted