Question 945791
I have a bit more information on my barrel question. 228lts approx 60gal.
Barrel Height = 89cm  Thickness of the barrel is 25mm
Belly Dia.  = 71cm Circ.= 223cm
Top & Bottom Dia. = 58cm Circ. = 182cm
Question 1- What is the internal surface area?
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The belly diameter is only 13 cm more than the top and bottom, so using the average for the diameter will cause a small difference.
(58 + 71)/2 = 64.5 cm avg diameter
--> Outside dimensions: r = 32.25 cm
h = 89 cm
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Inside dimensions: r = 32 cm, h = 88.5 cm
Inside SA = {{{pi*r^2 + pi*r^2 + 2pi*r*h}}} (bottom, top & sides)
= {{{2*pi*1024 + 2*pi*32*88.5 = pi*(2048 + 5664) = 7712*pi}}} sq cm
=~ 24228 sq cm
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Question 2- What is the surface area of liquid in contact with the surface of the inside of the barrel?
If it's full, it's the same as above, 24228 sq cm.
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I need to be able to work out the equivalent area for a 1lt jar with a piece of wood in it to have the same ratio as the liquid in the barrel.
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24228 sq cm/228 liters --> 106 sq cm per liter