calculating volume

[Simon Desarte]

I am getting very frustrated with trying to put the formula for
calculating the volume of a solid cone and was wondering if anyone can
help me.

I can do it on paper but can't seem to get it to work in excel!
I have installed the analylis tool pack to give me all the SQRT
functions etc

I do have one criteria that is constant and that is the height of the
cone shape which will always be 10cm.

So I would like to enter the first circumference in cell A1 and then
the second circumference in cell B1 and get the answer in C1 (allowing
for the height to always be 10cm).

I.E. circ1= 25cm circ2= 30cm height = 10cm

Any help would be most appreciated

Kind regards

Simon

 

[Kevin Stecyk]

Simon,

This looks a lot like a homework problem. Unfortunately, we don't do
homework.

But I will give you some hints:

The volume of a cone is 1/3(Area of Base)(height) = 1/3(pi r2)(height).

You are going to need to transform circumference to radius. (pi * 2 * r =
circ)

You are going to need to determine the heights of your cones. You know the
two radii and you know the distance between, so thus you know the cone
heights. You have one large cone less a smaller cone. In other words, you
need to calculate the volume of a cone as though it were not cut off
prematurely. That will be the large volume. And then you need to calculate
the volume of the portion that was cut off.

And then you can solve your question.

<<I can do it on paper but can't seem to get it to work in excel!>>

If you can do it on paper, you can do it Excel. Just put the same formulas
in place.

Good luck!

Kevin

 

[Simon Desarte]

Thanks for your posting Kevin, If I give you a bit of background into
what I am trying to do it might make people realise it is not
homework.

I need to calculate the volume of peoples legs before and after
vigorous exercise (strange but true). I don't need it to be totally
accurate so a cut of cone formula is perfect.

I have uploaded my paper calculations here
http://simon_desarte.tripod.com/cone.gif

I want to put the bottom formula into excel but I can't seem to make
it work!

I can't seem to make any formula work in excel even =1/3(pi()
radius^2)(height)where I have substituted "radius" for a number and
"height" for a number.

It comes back telling me that I have typed it in wrong.

Please can someone help me it is driving me crazy I admit to never
using excel before but I need to do the calculations on a computer.

Thanks for your help

Simon

 

[Andy B]

Simon

I have set up the formula you have described and it works OK. I've used:

=25/PI()/2*10/3

This is just a long-hand version of what you require (for the 25cm cone).

Andy.

 

[Kevin Stecyk]

Simon,

I will send you a spreadsheet with the math already figured out.

Regards,
Kevin

 

[tansikamalar]

Cone is a three dimensional shape that has a single elliptical or circular base and an apex.
Volume of cone formula is explained in http://www.easycalculation.com/maths-dictionary/cone.html.