Surface area?

[NJ Devils Fan]

(|
That is what the tank basically looks like. The bent part is a semi sircle because a circle doesn't have to be perfectly round like this-o. It can also look like this- 0, or this- ().

 

[carpguy]

The bow is an arc, not a semicircle (halfcircle). If the bow was a semicircle the tank would be 36" wide at its widest and the center of the circle would be in the plane of the front corners. The circle the bow is part of is about 8.5 feet in diameter and its center is about 2.75 feet behind the tank. You're figuring for a rectangular tank with a small bump out in the middle.

 

[Fishiebusiness]

Originally posted by NJ Devils Fan
(|
That is what the tank basically looks like. The bent part is a semi sircle because a circle doesn't have to be perfectly round like this-o. It can also look like this- 0, or this- ().

The formula you state: ((pi)R squared divided by 2) applies only to perfect half circles, not to half ovals, half ellipses, or half zero's.

 

[Gumby7]

Originally posted by Fishiebusiness


As stated, the bow is clearly not a semi circle. Its a small slice of one side of a circle that has a radius much larger and harder to determine than from the length of the tank.

Just trust gumby and his AutoCAD, it works!

Thanks for the vote of confidence!

PS the radius is 51" and the center point is 33" behind the back of the tank. If you're still interested you can verify this by placing the tank on the floor mark out the center point 33" behind the tank. Then hold the zero end of a tape measure on that point and try to sweep the front bow radius as 51".

Check out http://www.constructionworknews.com/field-manual/1-2.html "Segment of a circle" to get a feel for why is not as simple as pi*r^2.

PSS I be sceptical of that lighting equation. I see no good reason why the "divide by 11" is not already factored into the 0.12 etc factor. That is, why not use 0.0109 instead of 0.12/11? Are you sure something isn't missing like a pair of brackets? Often formulas which require two lines (like a denominator and a numerator) get screwed up on websites due to font issues etc.

Gumby7.14159265...

 

[Skittyfish]

The formula came from www.thekrib.com
eiither in the plant area or the lighting, I can't remember. and it could have had something else.

Sorry to create such a ruckus..


Thanks for your replies