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# Density: Formula and units 0%

Summary

# Density: Formula and units

## In a nutshell

​Density is a measure of how heavy $1cm^3$ of a material is. Another way of saying this is that density is the mass per unit volume of a material. Every material has its own density.

## Density formula

The density of a material is given as:

$density=\frac{mass}{volume}$

Or, more simply:

$D=\frac{M}{V}$

## Units of density, mass and volume

#### Units

Density

kilograms per cubic metre ($kg/m^3$​), grams per cubic centimetre ($g/cm^3$​)

Mass
kilograms ($kg$​), grams ($g$​)
Volume
cubic metres ($m^3$​), cubic centimetres ($cm^3$​)

## Solving density problems

​To solve problems involving density, follow this procedure:

#### procedure

 1 Identify what values you have and what variable you want to find. 2 Rearrange the density formula for the desired variable. 3 Substitute in known values. 4 Give the answer with the correct units.

##### Example 1

The density of gold is $19{,}300kg/m^3$. A bar of gold weighs $4{,}000kg$. What is the volume of this bar to two decimal places?

From the given information, identify the density and the mass:

$D=19{,}300kg/m^3,\,M=4{,}000kg$​​

Write down the density formula:

$D=\frac{M}{V}$

Rearrange the density formula for volume:

$V=\frac{M}{D}$​​

Substitute in the known values:

$V=\frac{4000kg}{19300kg/m^3}$​​

Give the answer with the correct units:

$V=0.207253886...m^3$

Round to two decimal places, like the question asks:

$\underline{V=0.21m^3}$, to two decimal places.

FAQs

• Question: What is the formula to calculate density?

Answer: The formula to calculate density is: Density = mass/volume.

• Question: What is density?

Answer: Density is the mass of a material per unit volume.

Theory

Exercises