On Fri, 01 Sep 2006 00:18:05 +0200, herby1620 <
herby1620@...> wrote:
> Thickness in um =
> 0.5 ∗ 10000 454
> ---------------------- ∗ ---- = 17 um
> 2.54 ∗ 2.54 ∗ 16 ∗ 144 8.94
> Some of the numbers used (for reference):
> 0.5 = ounces/sq-foot (amount of copper)
> 10000 = um/cm (microns per cm)
> 2.54 = cm/inch
> 16 = ounces/pound
> 144 = square inches/square foot
I certainly know _why_ i love the SI! That's just frightening...
I certainly also love google - enter the following line as a search term:
8920kg/m^3∗1ft^2∗35micrometer in oz
and you get
1.0230976 ounces
The good thing about google calculator is it can deal with units and do
the conversions for you. And if you have a mistake in the formula, like
divide somewhere instead of multiplying, the result will just not come out
in the correct unit. If i do that on paper i need to engage brain to check
that....
Sadly it does not (yet) know the density of copper automatically it seems.
ST