# Question #93539

##### 1 Answer

Here's what I got.

#### Explanation:

I was able to track down a very similar problem, check it out

The screen is taken from here - page 81

http://rjfisher.lgusd.org/ourpages/auto/2014/6/30/59485755/Student%20ebook%20Chapter%204.pdf

The idea with this type of problems is that you need to use the dimensions of the piece of wood to determine its *volume*, then use the given mass to find its density.

So, the volume of a rectangular prism is given by the formula

#V = l xx h xx w" "# , where

In this example, you have a piece of wood that is

#V = "5 cm" xx "3 cm" xx "2 cm"#

#V = "30 cm"^3#

Since density is defined as mass per unit of volume, the piece of wood will have a density equal to

#rho = m/V#

#rho = "20 g"/"30 cm"^3 = color(green)("0.67 g/cm"^3)#

You can check out a list of species of wood listed by their density here:

http://www.engineeringtoolbox.com/wood-density-d_40.html

So, what were the two factors that determined the wood's density? The mass of the piece of wood and its volume.