# looking for a formula for calculating weight



## zauggart (Jun 18, 2008)

hi there
im looking for a formula or method of calculating weight of a metal if i know the metals weight in a given size or not . here is what i mean take the flat packs for instance and if you could get all the strands of fine gold wire out of one in and lay it all down end for end and say you had 6 feet of this with the diameter being lets say 1/1000 of an inch . how can i calculate the weight of it? what would it be ?? area x atomic weight ?
any help would be great
thanks
Ian


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## OMG (Jun 18, 2008)

Pure gold weighs 19.3 grams per cubic centimeter. Check wiki for other metals densities.
So you could calculate the weight of a pure gold wire of that size, but you don't have pure gold. so the numbers will be off.

A cylinders volume (the wire is a cylinder) is:
3.14*radius*radius*length
so
3.14*0.001*0.001*72
(72 = 6 feet specified in inches)
= 0.00022608 cubic inches
which converted to cubic cm (1 cu in = 16.387 cu cm)
= 0.0037 cubic cm.
now we have the volume of the wire specified in cubic cm.
all we have to do is multiply by its density of gold (19.3 grams/cu cm)
== 0.0715 grams
Thats if it was 100% gold.

So the easier way to say it is if you want the weight, you have to know the volume. (just multiply the volume by the density - make sure the units are the same. use cm and cubic cm for everything - its easier). You can look up the formulas for finding the volumes of different shapes (ie cube, sphere, cylinder, cone, etc.)


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## jerrydees (Jun 18, 2008)

Hi Ian,

I use this metal weight calculator.

http://www.geocities.com/alcomet2000/calculate.htm

Jerry


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