Science Lab Investigation on “Density Clay”
International School of Myanmar
Grade 8
How does the mass of a block of clay affect its density?
Done By : Susan, Kyaw Kyaw Lin, Aye Myat
I.
Question
What is the effect of mass, on density in terms of how a block of clay can stay afloat?
II.
Hypothesis
The more the mass of the clay, the greater the density of the clay is than the water which is
a directly proportional relationship.
III. Experimental Procedure / Materials
Materials
-
Basin ( or big plastic container)
A block of clay
Washers ( 5 grams each)
A weighing scale
Procedure
Firstly, fill your basin with water until the half of the container. Then you place your block of clay and see
if it floats or sinks. According to your first results, adjust the shape of it , or the volume of it so that it
stays afloat. Then measure the volume of the clay by multiplying its length, width and height once you
are satisfied with the shape. Then, slowly place washers on top it and record how many washers it can
hold before it sinks. You can do as many trials as you want to get the highest number of washers.
IV. Data ( Graph and Table)
Mass of Clay (g)
Mass of load(g)
Total mass (g)
Volume (cm3)
Density
1
135
20
155
392
0.39
2
135
40
175
392
0.44
3
135
60
195
392
0.49
4
135
80
215
392
0.54
5
135
100
234
392
0.59
6
135
120
255
392
0.65
7
135
140
275
392
0.70
8
135
160
295
392
0.75
9
135
180
315
392
0.80
10
135
200
325
392
0.82
In this table, it portrays that the mass of the clay is constant at 135 g and when we add more load or
washers, it increases the total mass, thus, creating a rise in the density level. In this case, the volume of
the clay is stable because we want to measure how the mass affects the density. The amount of load is
added by 20 grams and in the end; we found out that our block of clay could bear a mass load of 200
grams or 40 washers before it sank.
Interpretation
This data in the graph shows that as the mass increases, the density of the clay block increases
correspondingly. This is a directly related proportion and increases little by little. But, at a certain point,
the clay will sink because of too much load, so in that case, we would want to increase the volume to get
the density of the clay lesser than the water’s density, which is 1gm/cm3. When we increase the volume
by expanding the surface, it will be able to hold more weight and therefore, the amount of mass can be
increased. But according to this graph above here, it shows the relationship between the mass and the
density, in which volume would be an external factor to think about later.
Conclusions, or Learning Insights
In conclusion, we figured out that the more the mass of the object, the more the density which
is directly related which proved our hypothesis right. But if the volume increases, it decreases the
density of the object which is inversely proportional. So there are many factors or variables that can
affect the density level. When we wanted to float the slab of clay, we had to decrease the volume by
making the surface a flat one. The flatter it is, the better it floats and is able to bear more load such as
the washers. In the end, we found out that our clay block was able to hold 40 washers of 200 grams,
which was satisfactory. We could increase the volume more, to be able to hold more, but we decided
that this was a pretty good number and kept it the same way. First, we were confused with how density
and mass works , even though we understood the concept theoretically as both are similar and they
mean how much packed or the amount of stuff in an object. But, now we understand that density is not
only about mass, volume is another variable involved. Density depends on the mass and the volume, if
one of the two varies, the density will consequently change. It was a fun experience and I learned a lot
from it because I realized that density was everywhere in our everyday lives and it is just we are
unaware of it. We had a fun time, changing the shape of the clay, splashing water to each other and
playing around. But we would like to recommend getting the lengths, the volumes and the
measurements accurate for it would change the rest of the results. Also, make sure that the final volume
of your clay block stays the same for all the trials. Overall, it was a beneficial and a great learning
experience of Density!
Discussion ( Density, Relationship and daily use)
Density is basically the amount of mass per unit of volume. It measures how compact an object
or liquid, based on a certain amount of volume. This shows that if the volume or the mass varies, the
density itself will vary. The way to compute for Density is Mass divided by Volume. Density, Mass and
Volume are very much related to each other in the field of Physics. The more the mass, the more the
density it is which a direct relationship is. But the more the volume, the less the density it is. This
however is inversely related. Between mass and volume is that the more the mass, the more the volume.
It is a widely used physical property of matter and is a very significant topic which helps us in our
everyday lives, in many different ways. The most evident one is how a ship looks in water. Ships stay
afloat because they hold ballast tanks filled with air particles, which create a bigger volume, and
therefore, it becomes less dense than the water. Furthermore, a submarine also applies the idea of
density. It can either sink or float by pumping water in and out so that it becomes less dense than the
water. In addition, plumbing systems are a very well-known application of density. When fluids with
great density flow through water, it flows with a lower velocity, pressure and height. However fluids
with less density have higher velocity and all the other characteristics. So, engineers use this concept a
lot when they design dams and large-scale plumbing projects. Also, the weight distribution on board the
aircraft changes as the engines consume fuel, so the density of the plane is not uniform anymore. This
causes a shifting center of mass, and pilots must make adjustments during flight to account for these
changes.
References
www.everydaylife.globalpost.com/can-study-density-used-real-world.com
www.newton.dep.anl.gov
ww.wiki.answers.com/Q/How_is_density_used_in_everyday_life
www.www.scienceclarified.com/everyday/Real-Life-Chemistry
www.wikipedia.com