Chapter 4 - Density and Buoyancy
Mass & Volume
Home Page for Chapter 4
A Quick Review and How to Measure
What is Density/Calculating Density
What is Buoyancy? / Buoyancy in everyday life.
By now you should know what to find here
Before you can understand density you need to know about mass and volume.  
Let's Review:
Mass
Mass is the amount of matter in an object.

Mass is always measured on a balance.  The triple beam
balance show here is the type we will be using in several
lab settings.  
The electronic balance
will be used also.
Mass in measured in
grams or Kilograms!
Volume - Solids
Simply put, Volume is the space that matter takes up.  There are two easy ways to measure the
volume of a solid.

O.K.  I know that math is not considered easy by some of
you, but if you use a calculator and the proper formula it's a
pretty simple way to get the answer.

In this class we will only be using one formula, the formula
for finding the volume of a rectangular solid.

Volume = Length x Width x Height

Because you are multiplying cm x cm x cm the label for
your numbers will be in cubic centimeters or cm
3
Way #2 - Displacement

We have already see that we can measure the volume of a liquid using a
graduated cylinder.  We can also measure the volume of a solid that way
Displacement means to push out of the way.  We see displacement when we
get into a bathtub.  The water level rises by the volume of the 'us' that we put
in the water
If we put a solid object into a liquid,
the solid will
displace it's volume of
beginning from the ending amount
of liquid we have the volume of the
solid.
Volume - Liquids
Nothing could be easier than measuring the volume of a liquid.  You pour it
into a graduated cylinder and your done!!

There is one small catch though, the liquid may look like it is 'curving', if you
notice this you just look for the bottom of the curve (called the
meniscus)