## Intro: The Density Formula

The Density Formula, how to find the density of an object.

You will need:

1. Scales (for weighing)

2. A cup or beaker with ml measurements (L measurements would work but ml's is optimal)

3. Water (if using irregular shape)

4. Weight (must fit in cup/beaker with whatever your weighing, used to sink floating objects)

5. What you're measuring

6. Paper & pen/pencil (if you need it to do calculations on paper)

## Step 1: Measuring

The formula to find the density of an object is relatively simple. First you must find its weight, using scales or any other weighing device. Next you have to find its volume, if it's a regular shape you could use a ruler but if it's irregular (E.G. a rock) you could use water. By filling your measuring cup/beaker with water (leave room for object, record how many ml's it's at) then adding the object (record how many ml's it's at now, make sure the object is submerged and the water hasn't overflowed) you can get your calculations. Minus the first measurement from the second one (E.G. Second measurement - first measurement), now you have the volume. If the object is lighter than water, get your weight (Physical weight, E.G. A fishing sinker) and measure its volume using the method shown before, now add the light one that floats then the weight. It should sink, now get those measurements and do this calculation (end volume [both weight and object] - weight [E.G. Sinker]), with that minus the volume of water from the answer you just got (E.G. The answer you just got - volume of water). Now you have the volume of an irregular shape. Remember, (1ml = 1cm3).

## Step 2: Calculations

The calculations you now have are very simple.

Density = Mass ÷ Volume

Divide Mass by Volume, you now have the density!

## Step 3: Written Answer

Finished answers are written by having the [Weight] then a [/] then the [mass] (E.G. cm3). The weight is per point of volume, E.G. Per 1 cm3. (1 ml = 1 cm3)

Example of how it's written:

Mass/cm3

(cubed sign is because it's a 3D object)

## Discussions

2 years ago

So if density had been a concept unacquainted to the general knowledge at the time of Archimedes, how was he so joyful upon discovering displacement of liquid? That should have only part of the puzzle. He would need to know 2 things:

That gold and some other metal had different densities.

And he would also need to know a method of determining densities.

He only discovered the method of determining densities by using liquid displacement. This was something, of course, but without the partner knowledge, it hardly merits running naked through the streets of Syracuse shouting "Eureka!".