3. Rationale
In the blueprint for my prototype, I have a balloon taped to the
inside of a plastic bowl. The balloon is then surrounded by aluminum
foil (and around the outside of the bowl). On top of the balloon, there
is a paper cup with tape running through the bottom of it all the way
around the balloon. The plastic bowl is about 12.7 centimeters of a
diameter across, and has a 7.6 centimeters diameter base. It is about
3.8 centimeters in height. The balloon has a circumference of 35
centimeters and the cup stands 5.7 centimeters tall.
I decided to use the plastic bowl to support the balloon so it
doesn’t become unbalanced as much when the weights are put on the
boat. I decided to use the balloon because it has a small mass and a
large surface area. This allows it to displace a volume of water equal
to its mass very easily. This will let it float easily. I decided to use the
aluminum foil so that the parts of the bowl that the balloon does not fill
can be covered. This way, the boat won’t start filling with water as
soon as it starts to sink a little bit. It will cover the whole outside of the
bowl so that the water doesn’t come up under the edges of the
aluminum foil and start filling the bowl that way. I chose to use a paper
cup to have somewhere to put the weights. I put it on the center of the
balloon so that it wouldn’t become unbalanced. I ran tape through the
cup and around the balloon so that the cup won’t fall over as easily
when filled with more weight. I taped the balloon to the inside of the
plastic bowl so that it doesn’t move and cause the cup to topple or spill
over.
4. Data Table of Results
Mass of
Mas
s
the
Boa
t
Hel
d
(g)
the Boat
(g)
Trial
1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 Trial 8 Trial 9
Trial
10 Average
34.9 g 12.5 12.5 10 10 15 17.5 15 20 17.5 12.5 14.25
Qualitative
Data
The boat started tipping over before any mass was added because the cup unbalanced it (was too big for the size of the bowl).
For most trials, after 5 pennies were added the boat began
tipping farther and faster. It was noted that the more waterlogged the two sides of the boat became,
(evenly) the less unbalanced the boat became.
