This is the Archimedes Principle experiment.
Just as the extra credit stipulated, I
am going to test Archimede's Principle on
3 types of ice: first, I am going to use regular
ice, then I am going to use ice with a nail
inside.
Finally I am going to use ice with a pocket
of air inside.
So for my pocket of air , it was a little
difficult to create...so I used a plastic
ball of a known diameter, and a very negligible
mass and I put it inside and froze the ice
outside.
The ball is occupying the space that the air
would occupy.
-if you would say- and I am going to use measuring
cups and just for consistency- I am going
to fill all my cups up to the 250 ml mark
when I put the ice.
So I am going to start: this is the regular
ice, this is 250 ml ......ok yeah so it reached
250 ml now I am going to measure the rest
of the water , which is experimentally the
volume displaced by the ice ... so it's 70...73.2
ml ...(writing data down)...so now, I am going
to do the second part ... Second Ice (Ice
with nail)....Repeating the same procedure...
3rd ice, ice with a pocket of air .... repeating
the same procedure....so, our ice is done
melting ...I don't know if you can see clearly
but for the first cup , this one, the we put
the regular ice, as predicted, the level of
water did not change . as we can see, it's
still at the 250 ml mark.
And, for the second one, it is almost at the
250 ml mark, this is the one with the nail
inside, so when I remove the nail , it probably
going to drop just as predicted, because the
volume of the ice melt is less than the volume
displaced by the ice and the nail, (removing
the nail) so as we can observe , if i zoom
in...( sorry I did not know that I was not
showing the cup), after removing the nail,
the water level is now a little below the
250 ml mark, so now I am going to measure
the final volume of the water to compare with
my theoretical values.
so, for the regular ice, I am measuring the
final volume...as we can see the final volume
is right at ... 250 ml and that's just where
we want it to be.
Notice that I am subjecting myself to error,
because , first I am not using vey precise
instrumentation, but also reusing the same
graduated cylinders, some droplets of water
are remaining , so this will influence my
results.
Now I am going to measure the final volume
for the ice with the nail. so as we can see,
from here, (trying to focus the camera), Ihope
you guys cans see but it's right at 240 ml
...240 ml ... 240 ml mark , that's the final
volume for the ice with the nail.
So, as for the ice with the pocket of air,
as we can see, after it has melted, it still
around the same level , the 250 ml mark, theoretically
it should be little less but when you think
about it ( the amount of volume the air occupies
is very minimal compared to the ice), and
that's why the volume displaced should still
be around the 250 ml mark.
I will go ahead and measure the final volume.
ok so, for some reason, the final volume is
260 ml , so my first two experiments went
very well, the one with the regular ice and
then the one with the nail inside the ice
but as for the last one ( with pocket air)
, for some reason I kept getting more water
than I should for the final volume.
I repeated the experiment two more times but
I kept getting the same results.
And thinking about the possible errors, I
thought, probably, using the ball to create
a pocket of air is not such a good idea, first
of all.
Because real air , once the ice melts, doesn't
occupy space, it dissipates ... I think using
the ball to create a pocket of air was not
a good idea for this part.
but other than that I got pretty decent errors
on all of my trials, so I am happy with the
experiment.
