# Question 651d1

Jul 22, 2015

Density: ${\text{0.52 kg/m}}^{3}$

#### Explanation:

So, you know that you're dealing with an object that has a certain mass and a certain volume.

You weigh the object and determine that it has a mass of 22 kg. Likewise, you measure the volume of the object and determine that it occupies ${\text{42 m}}^{3}$.

Density is defined as mass per unit of volume. In other words, density tells you what the mass of one unit of volume is for a given object.

SInce you measured the volume in cubic meters, the unit of volume will be ${\text{1 m}}^{3}$.

So, to get the object's density, you need to determine what the mass of ${\text{1 m}}^{3}$ is. To do that, use the fact that you know what the mass of ${\text{42 m}}^{3}$ is

1cancel("m"""^3) * "22 kg"/(42cancel("m"""^3)) = "0.5238 kg"#

If one cubic meter has a mass of 0.5238 kg, then the object's density will be

$\rho = {\text{0.5238 kg"/("1 m"""^3) = "0.5238 kg/m}}^{3}$

Rounded to two sig figs, the number of sig figs you used for your two measurements, the answer will be

$\rho = \textcolor{g r e e n}{{\text{0.52 kg/m}}^{3}}$