# how to find the thickness and/or the layers of atom that an aluminum paper has?

• Oct 9th 2009, 11:47 AM
Julian.Ignacio
how to find the thickness and/or the layers of atom that an aluminum paper has?
how to find the thickness and/or the layers of atom that an aluminum paper has.

• Oct 9th 2009, 12:21 PM
e^(i*pi)
Quote:

Originally Posted by Julian.Ignacio

Do you actually have a problem in front of you?

The usual way to find thickness is to find out the mass, divide by the density and then divide by the area.

$l = \frac{m}{\rho A}$

To find the layers of atom you'd then divide by the atomic radius (and since atomic radii are usually measured in pm you'll get a lot of them

$n_{\text {atomic layers}} = \frac{m}{\rho Ar_{atom}}$

Note all units should be SI
• Oct 9th 2009, 12:25 PM
Julian.Ignacio
It wouldn't be a problem IF we knew how to do it; the teacher told us to search in the internet, in books or ask a friend to find the answer. In short I don't really have to do the exercise, but due to my curiosity, i'm trying to do it (Wink). Thank you for the answer!! =)
• Oct 9th 2009, 12:29 PM
e^(i*pi)
Quote:

Originally Posted by Julian.Ignacio
It wouldn't be a problem IF we knew how to do it; the teacher told us to search in the internet, in books or ask a friend to find the answer. In short I don't really have to do the exercise, but due to my curiosity, i'm trying to do it (Wink). Thank you for the answer!! =)

I should point out that I made the assumption that the aluminium is spread out uniformly, ie: all parts are equally thick. This is usually the case and a safe assumption to make unless told otherwise
• Oct 9th 2009, 12:38 PM
Julian.Ignacio
Quote:

Originally Posted by e^(i*pi)
I should point out that I made the assumption that the aluminium is spread out uniformly, ie: all parts are equally thick. This is usually the case and a safe assumption to make unless told otherwise

It's got a square-shaped figure, so i'm assuming that your answer's correct (Happy) thanks.