Finding the surface Area

R

Richard

If I have a tube thats .805 round, 1.235 high, .060 thick. How would I
write this as an excel formula. Thanks in advance!!
 
J

joeu2004

If I have a tube thats .805 round, 1.235 high, .060 thick.
How would I write this as an excel formula.
Click to expand...

Not sure what you mean by ".805 round".

If 0.805 is the outer circumference, you don't need thickness. If A1
is 0.805 and A2 is 1.235, then the surface area is: =A1*A2.

If 0.805 is the inner circumference (seems unlikely), then the outer
diameter is the inner diameter (0.805/pi) plus 2*0.060. If A3 is
0.060, then the surface area is:

=PI()*(A1/PI() + 2*A3)*A2

which can be simplified algebraically to:

=(A1 + 2*A3*PI())*A2

If 0.805 is the inner diameter, then the outer diameter is simply
0.805 plus 2*0.060. Then the surface area is:

=(A1 + 2*A3)*PI()*A2

Hope one of those works for you.
 
R

Richard

Apparently, you did not bother to read several good answers.

Bill
Click to expand...

YES Bill, I did read both answers, May I ask WHO you are. Apparently
you seem to know everything. But you never seem to give any support
other than criticism . Other than giving smart ass remarks. You know
something BILL, These newsgroups are designed for people like me,
someone thats not as smart as you but still needs a little help now
and then. So Bill If I don't seem as smart as you it's because...
Well, I'm probable not. Just someone trying to learn at my own speed.
Is that OK with you. From now own, don't respond to any of my
questions. So Piss off, ASSHOLE!
 
R

Richard

The information is ambiguous:

? Do you want total surface area = inside + outside?

? Are the ends open?

? Do you also want the area of the edges at the ends?

The formula for the area of a cylinder with height H and radius R is:

        Area = (pi) x 2R x H

The formula for the area of a circle of radius R is:

        Area = (pi) x R^2

To get the edges at the ends, subtract the inner circle from the
outer.
Click to expand...
It might seem ambiguous but tried to keep it simple
Yes to your first, second and third question. If it's open which I
stated that it's .060 thick. If it's .060 thick it would have to be
open which would include the total surface area meaning inside and
out. The areas outside are also still part of the total surface area.
Thanks for your help but Bill has really pissed me off. So never mind!
 
K

Ken Mintz

If it's .060 thick it would have to be open which would include
the total surface area meaning inside and out.
Click to expand...

Oh, I didn't think of that. So if "0.805 round" refers to the outer
circumference, the outer surface area is simply 0.805*1.235. If A1 is
0.805 and A2 is 1.235, then in Excel: =A1*A2.

For the inner surface area, we need to determine the inner diameter.
That's the outer diameter (0.805/pi) less 2 times the thickness. So
the inner surface area is (0.805/pi + 2*0.060)*pi*1.235, which can be
simplified algebraically to (0.805 + 2*0.060*pi)*1.235. If A3 is
0.060, then in Excel: =(A1+2*A3*PI())*A2.

If B1 and B2 have the formulas for the outer and inner surface areas,
the total is: =B1+B2. Or you simply combine and simplify the
formulas, to wit: =2*(A1+A3*PI())*A2.

Double-check the algebra. I have not tested any of this. The key
formulas are: c = d*pi, and A = c*h, where d = diameter, c =
circumference, h = height, and A = surface area.
 
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