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Old 02-11-2012, 12:54 AM
zptaiopdhnfcre zptaiopdhnfcre is offline
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lbs per sq. ft.

i once knew this question;

how many lbs. does it take to sink 1 sq. ft. 1 inch ?

thank you !
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Old 02-11-2012, 02:10 AM
dougfrolich dougfrolich is offline
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Sink it into what?

If you take an ave. seawater density of 64lbs./ft^3 then it would take 5.33 lbs.
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Old 02-11-2012, 06:59 PM
zptaiopdhnfcre zptaiopdhnfcre is offline
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whoops............!

sorry !
i take it it must be a different number# of calculation for fresh water and salt water ?
are the numbers of lbs. different ?
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Old 02-11-2012, 07:14 PM
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troy2000 troy2000 is offline
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Quote:
Originally Posted by zptaiopdhnfcre View Post
whoops............!

sorry !
i take it it must be a different number# of calculation for fresh water and salt water ?
are the numbers of lbs. different ?
Yes. Salt water is denser, so it takes more weight to displace it. Whether that's significant or not depends a lot on what you're playing with... you may not even notice it with a canoe, for example. But a cargo ship has separate Plimsoll lines to indicate its maximum load capacity in fresh water and seawater, among other variables.
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Old 02-11-2012, 07:34 PM
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Quote:
Originally Posted by zptaiopdhnfcre View Post
i once knew this question;

how many lbs. does it take to sink 1 sq. ft. 1 inch ?

thank you !
What is the question, how much to sink a sq inch or a sq foot?

If you once knew the answer you would think you would know the question.
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Old 02-11-2012, 09:41 PM
DCockey DCockey is offline
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Archimedes principle. Buoyancy of a floating object equals the weight of the volume of water displaced. A volume of 1 sqare foot x 1 inch is 1/12 of a cubic foot. Sea water weighs approximately 64 lbs per cubic foot. Fresh water weighs approximately 62.4 lbs per cubic foot.
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Old 02-12-2012, 12:30 AM
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Wynand N Wynand N is offline
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when will the Americans learn that metric is the way that makes the world tick...?

What is simpler than 1 liter of water = 1 kilogram. One cubic metre (1000 lt) = 1000kg For decimals - just move the point.
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Old 02-12-2012, 04:01 AM
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Our foreheads are thick and our brains are small...maybe we'll catch on by the time we step foot on Mars.
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Old 02-12-2012, 08:01 AM
rberrey rberrey is offline
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It,s like a railroad track and a Roman road , if it,s not broke dont fix it.
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Old 02-12-2012, 11:00 AM
DCockey DCockey is offline
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Originally Posted by Wynand N View Post
......

What is simpler than 1 liter of water = 1 kilogram. One cubic metre (1000 lt) = 1000kg For decimals - just move the point.
Only if fresh water. Density of salt water is not a nice, round number in the metric system.
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Old 02-12-2012, 01:39 PM
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Only if fresh water. Density of salt water is not a nice, round number in the metric system.
Salt water: SG = 1025kg per cubic meter

1 liter = 1.025kg and one cubic meter (1000lt) = 1025kg
Because meter cube it is a thousand liter units (three zeros), the decimal get moved 3 places, simple as that...
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Old 02-12-2012, 05:52 PM
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Originally Posted by Wynand N View Post
Because meter cube it is a thousand liter units (three zeros), the decimal get moved 3 places, simple as that...
Now you're just showing off.
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Old 02-12-2012, 06:37 PM
zptaiopdhnfcre zptaiopdhnfcre is offline
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thanks

hey thanks for all the info !
you people really try to help.

thanks.
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Old 02-12-2012, 06:50 PM
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Quote:
Originally Posted by Wynand N View Post
when will the Americans learn that metric is the way that makes the world tick...?
Well ... I believe it was Jimmy Carter who mandated the conversion ... and we did actually see some providers of petrol convert to liters ... but that was just to disguise price changes ...

You're right of course. We're very obstinate. On the other hand, we're also very talented ... we can use both
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Old 02-12-2012, 06:57 PM
zptaiopdhnfcre zptaiopdhnfcre is offline
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does anyone need a fiberglass laminator or a mold maker ?
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