How To Calculate The Thickness Of Aluminum Foil

Aluminum foil, an everyday item used to keep food safe in the kitchen, is possibly the thinnest material in your home. Manufacturers of aluminum foil often provide the width and length of the foil roll on the package, but the thickness of the foil is often not advertised or displayed. Instead, it's common to see labels like "standard duty," "heavy duty" and "extra heavy duty" to describe foil thickness. It is difficult, but not impossible, to measure the thickness of such a thin material, and impossible to do with common measuring tools, like a ruler or a measuring tape.

1. Measure the Values

Use a ruler to measure the length and width of the aluminum foil in centimeters. Crumple the piece of foil into a small ball or fold it into a small shape and place it on a milligram balance to find the weight. Records the values on a sheet of paper or data table.

2. Remember the Relationships

Remind yourself of the relationships:

\(\text{density}=\frac{\text{mass}}{\text{volume}}\ \text{ }\text{volume}=\text{length}\times\text{width}\times\text{height}\)

When working out the thickness of aluminum foil, you are simply working out its height dimension. This simple formula allows you to measure the thickness of aluminum foil.

3. Calculate the Thickness

Use the formula:

\(\text{thickness} = \frac{\text{mass}}{\text{length}\times\text{width}\times\text{density}}\)

The density of aluminum is 2.7 g/cm³. So if you have a piece of aluminum foil that is 15 cm long and 20 cm wide and weighs 1.8 g, the calculation is:

\(\text{thickness} = \frac{1.8}{15\times 20\times 2.7}=0.00222\text{ cm}=2.22\times 10^{-3}\text{ cm}\)

4. Convert the Answer

Convert the thickness into inches if you desire to by multiplying the answer in cm by 0.39370, because 1 cm is equivalent to 0.39370 inches. In the example above, you would work out:

\(0.00222\text{ cm}\times \frac{0.39370\text{ in}}{1\text{ cm}}=0.000874\text{ in} = 8.74\times 10^{-4}\text{ in}\)