PHYSICS 101 Laboratory
Mass, Volume and Density
Name ____________________________
Date _____________________________
Table Number _____________________
Group Members______________________
___________________________________
___________________________________
Introduction:
In this experiment, you are going to determine what type of metal is used for different samples by the
method of density comparison.
Equipment needed: Density samples, vernier caliper, graduated cylinder(s), overflow bucket, catch container.
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A.
Q.
Obtain your density samples from the laboratory instructor. You may NOT mark the samples in any way. Devise a
way to identify each mass sample uniquely. All groups are to use the same identification method for each sample
so you and your group must communicate with the other groups. THIS MEANS YOU WILL HAVE TO TALK WITH
THE OTHER GROUPS.
What is the method used for identification purposes?
Find the mass of each sample and record the results below, in Table 1.
B.
For an initial measurement, which you will later use as the "true" density in determining the "percent error" of
indirect methods, you will find the volume of each sample by direct measurements of the sample's dimensions. As
a group, determine the formulary to use to calculate the volume of each sample. Record your measurements and
results of calculations in Table 1
Q.
What are the relationships you used to find the volumes of the samples? Show all of your calculations
here.
C.
We will also use a variety of indirect methods to determine the volume of each metal mass. These methods have
been historically employed for just this purpose. We will determine volume using indirect methods based on
submersion in a liquid (water) and determination of the amount of liquid displaced. We will continue to use the
measured mass for each sample.
1.
Obtain a graduated cylinder and pour an appropriate amount of water into it.
2.
Carefully put the density sample into the graduated cylinder and determine how much the water level has
risen. Record your data below in Table 2. Using this data, determine the densities of the samples.
3.
Now, we are going to use an even less direct method. In this case, we will not use a graduated cylinder, but
will investigate the mass of the water displaced by the samples and from this and the known density of water,
determine the volume of water displaced.
4.
Obtain an overflow bucket and use an appropriate container to catch the water displaced when the samples
are placed into the bucket of water. Find the mass of the overflow water, and record in Table 3. From the mass
measurement, determine the volume of each sample. (The density of water is found in the density table following
exercise H). Determine the density of each sample and finally show the %error of these results with the "truth" of
Table 1.
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PHYSICS 101 Laboratory
Mass, Volume and Density
Q.
List and explain any expressions you use in the process of going from the mass of the overflow water to
the volume of the cylinder. Show all of your calculations here.
D.
Now, time for "feed back." Comment on the methods used. Mention the difficulty of each, the perceived accuracy
of each, the differences in "measured volume," the differences in "% error" etc., etc. Also mention the "utility" of
each method with respect to finding the density of some arbitrary object. Finally, how about possible sources of
experimental error with respect to each method?
E.
From the determined density, estimate what kind of metal each sample is by comparison with the Density Table
following exercise H, and record your results.
F.
Now, we are going to use samples of "immediate origin." Find three different types of rock and repeat the above
procedure for each. In selecting your rocks, avoid ones of obvious man made origin (e.g. concrete). Also avoid
rocks with excessive soil content - no dirt clods! Record your data in Table 5. In this case, use whichever method
of volume determination the group found to be the "best" in the previous exercise
G.
Calculate the average density for the earth. List the information you used to complete the calculation of earth's
density. If no one in your group knows, ask your instructor for any expressions you need for this task and record
them below. You will find the necessary facts about the earth in your text book.
H.
Compare this result with those of Table 5. Comment on (explain) any differences in the densities of Table 5 and
the average density of earth.
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PHYSICS 101 Laboratory
Material
Osmium
Platinum
Gold
Uranium
Lead
Silver
Copper
Brass
Iron
Tin
Aluminum
Water (liquid)
Ice
Mass, Volume and Density
Density - gms/cc
22.5
21.5
19.3
19.0
11.3
10.5
8.9
8.6
7.8
7.3
2.7
1.00
0.92
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