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ropnjoker
05-06-2006, 06:56 AM
I'm trying to determine the footprint (PSI) of a 15 foot diameter swimming pool. To do so, I need to convert the circle into square feet (I think) then knowing that water weighs approx 8 lbs per gallon, and the capacity is 5300 gallons, I have 42,400 lsbs total. but now I need the conversion to square feet. Can you help?:D

Robert Fogt
05-06-2006, 02:08 PM
PSI is pounds/square inch, so really its square inches you want.

The area of a cirlce is:

The radius is 1/2 the diameter:
15 foot / 2 = 7.5 foot

Calcuate the area:
3.14 * 7.5 * 7.5 = 176.625 square foot

Convert square feet to square inches:
176.625 square foot = 25,434 square inch

I calculate 5300 gallons as 44,230 pounds

44230 pounds / 25434 square inches = 1.74 pounds/square inch

So its 1.74 PSI

Unregistered
02-13-2007, 10:47 AM
Your wrong. If you trace the diameter with a yard stick you will find that it only equals out to 12.5683. By finding that and putting it into the Fibonacci Sequence..you will find that the total PSI is roughly 1.689999... repeating of course. :)

Unregistered
03-28-2009, 03:53 PM
I'm trying to determine the footprint (PSI) of a 15 foot diameter swimming pool. To do so, I need to convert the circle into square feet (I think) then knowing that water weighs approx 8 lbs per gallon, and the capacity is 5300 gallons, I have 42,400 lsbs total. but now I need the conversion to square feet. Can you help?:D

You may also want to take into account that atmospheric pressure is pushing down at 14.7 lbs/sq inch.

Unregistered
08-26-2009, 07:50 AM
5300 gallons x 8 lb/gallon = 42400 pounds not 42300

Unregistered
11-24-2009, 04:31 PM
FYI Water is 8.34 lbs per gallon. if your using 8 lbs per gallon you will be off by a lot.

Unregistered
04-27-2010, 07:25 AM
If you are looking for the psi at the bottom of this pool, you do not need to know the diamater, you only need to know the height. The diamater will tell you the total wieght of water in the pool but not psi. Take the height of water and divide it by 2.31. This will give you the psi at the bottom of the pool. If the water is 5' deep, the psi at the bottom of the pool is 2.16 psi

Unregistered
09-25-2010, 02:11 AM
im attempting to figure out how many square feet a 130 foot diameter dome thats 80 feet high ( approx 3 floors ) would i use the same calculations?

JohnS
09-25-2010, 02:55 AM
im attempting to figure out how many square feet a 130 foot diameter dome thats 80 feet high ( approx 3 floors ) would i use the same calculations?

It would work for the ground floor. Because of the dome shape, the upper floors will be progressively smaller circles, and you will have to lay that out in a side view, to derive the diameter for higher floors based on ceiling height.

Unregistered
09-25-2010, 11:21 PM
awesome thanx , just needed to figure that out because its confusing with the numbers a calculator will give you when you put it in making it seem hell of a lot larger

gomez_charles@yahoo.com
10-09-2010, 03:10 AM
i have a diameter of roll 35mm and width of the roll is 45mm and the core is 12mm, i need to convert diameter in to meter

JohnS
10-09-2010, 04:42 PM
i have a diameter of roll 35mm and width of the roll is 45mm and the core is 12mm, i need to convert diameter in to meter

1 m = 1000 mm, so the 35 mm diameter is 0.35 m

Unregistered
11-26-2010, 10:55 AM
I have a cylinder tube that is 36" in diameter and 40' long what is the square footage of the cylinder tube.

JohnS
11-26-2010, 02:07 PM
I have a cylinder tube that is 36" in diameter and 40' long what is the square footage of the cylinder tube.

36" = 3'
Circumference of cylinder is pi*3' = 9.425 ft
area is 9.425' x 40 ' =377 ft²

Unregistered
04-12-2011, 01:03 AM
2100 diameter change to square feet?

JohnS
04-12-2011, 02:49 AM
2100 diameter change to square feet?

(pi/4)*D² = 0.785 *2100*2100 = 3,463,000 ft²

Demunseed
09-25-2011, 06:43 AM
Could someone tell me what the DIAMETER of 100,000 square feet is?

JohnS
09-25-2011, 07:02 AM
Could someone tell me what the DIAMETER of 100,000 square feet is?

sqrt(4*100000/pi) = 356.8248 ft

Unregistered
04-28-2012, 11:01 PM
conversion of a 56" diameter to feet.

JohnS
04-29-2012, 03:05 AM
conversion of a 56" diameter to feet.

12 inches in a foot, divide by 12.