Hot Air Balloons
Background:
In our science class, we have been studying hot air
balloons and the relation between mass and volume
that makes them float. In this experiment, we are
trying to find the right combination of mass and
volume to make our balloons float.
Table 1: Possible Variables
Brainstorm possible variables, include as many ideas as
possible.
Possible Independent Variables
Shape of the top of the balloon.
Shape of the balloon.
Color that the Hot Air balloon is made of.
Amount of glue used.
the weight on the bottom that keeps it from tipping over.
Purpose:
The purpose of this experiment is to
determine the effect of the shape of the
balloon (independent variable) on _the
amount of hang time (dependent variable).
Highlight your top choice from the table above.
Remember, unused independent variables can be
very good controlled variables (Constants).
Table 2: Variables
Independent (Manipulated) Variable
The shape of the balloon
Choices of the Independent Variable (Range)
size
Dependent (Responding) Variable
hang time
shape
color
Units of the Dependent Variable
seconds
Controlled Variables (Constants)
Impact if they are not controlled
amount of heat
some go higher than others.
Research
Question:
same height lift off
biased test because if one is tested on a hill
What will happen if we make hot air balloons in different shapes?
temp of room when testing
more hot air pushing some up than others in different rooms.
Hypothesis:
If we make a hot air balloon into the shape of a bullet than it will have greater hang time than a hot air
balloon made into a cube because at the point of the bullet, the hot air will be contained because hot air will
rise into that point, while in a cube the hot air will push at all different angles, thus making the bullet shaped
balloon go higher.
Table 3: Materials Keep it brief, this is not the emphasis of the experiment.
all the spaces.
Qty
Size
You might not use
Item
8
30 in. by 19 in.
tissue paper
1
20 grams
glue stick
1
230 grams
Fire Maple Gas Container
1
?
Scissors
Procedure: Remember to include multiple trials.
1. Come up with a design for the hot air balloon.
2. Ask Mr. Manning for approval of design.
1. Construct hot air balloons out of eight pieces of large tissue paper.
2. place over cylinder that is directing the hot air towards the balloon.
3. Hold until the balloon reaches a certain temperature from the hot air.
4. Start timing the hang time for the first trial using a stop-watch.
5. End timing for the first trial the instant the balloon touches the ground.
6. Timers tell their time to the data-keepers.
7. Recorders record the data under the correct group so there will be no confusion.
8. Take pictures consistently throughout the whole procedure.
9. Next group brings balloon to the cylinder while other groups make any more adjustments to the shape or
design of their balloon.
10.
Continue the procedure for all groups until all groups have tested their balloon three times.
11.
Find the average of all the data.
Data
Table 4: Accumulated data for the whole test
Range 1
(4)
(Grace,
Sophia,
Lauren)
Range 2
(8)
(Gen,
Colton,
Alex)
Trial 1
(Seconds)
24
3
Trial 2
(Seconds)
26
5
Trial 3
(Seconds)
22
11
Average
(graph these
numbers!)
Seconds
24
6.333333333
33333
Make sure to include labeled columns with quantities and
units.
Table 5: Test Averages
Grace,
Sophia,
Lauren
Averages
24
Gen,
Colton,
Alex
6.33333333
3
Data (continued) Pictures of Balloon Designs Our hot air balloon had a point at the
end that would help contain the hot
air. That is what we thought before
the experiment.
Figure 1: Placing our hot air balloon over
the heat for the first try.
Try to label the picture using uniform
fashion. Drag the arrows below to
the appropriate locations.
It was very hard to communicate
with each other how to get to the
same level when setting the balloon
on the pole.
We used pink and green colors.
Figure 2: The hot air balloon that we are
comparing to.
They had a hole to put the pole in.
Our hot air balloon had an open end
that we fixed at the end of the first
trial.
Try to label the picture using uniform
fashion. Drag the arrows below to
the appropriate locations.
Their balloon was much larger than
ours because we overlapped while
they did not.
There balloon was a rectangular
prism.
They used three different colors; light
pink, hot pink, and light blue.
Figure 3: [Title of Sketch goes here]
Holding it even for them was much easier because
ours had a larger bottom.
Try to label the picture using uniform
fashion. Drag the arrows below to
the appropriate locations.
Our balloon was not even on both
sides.
Ours was very hard to fill with hot air
balloon because it had an open
bottom.
We held the pole half way in the
balloon
In our balloon, there was a lot of
wasted mass because we did not cut
off all the remains.
Data (continued)
Qualitative Observations
Our balloon was hot pink and green. Their balloon was light blue, light pink, and hot pink. At
first, our balloon had an open end and then we fixed it to make it fly higher than before. Our
bullet was shaped like a bullet. Their balloon was shaped like a rectangular prism. we held
the pole half way up our balloon and they held it barely in their balloon.
Figure 4: [Put a picture of the setup with the
burner and your balloon]
You can see the balloon
start to fill up with hot air now.
Pole of the burner. Unfortunately, you
cannot see the burner.
Try to label the picture using uniform
fashion. Drag the arrows below to
the appropriate locations.
We held the
testing in a white
room with lots of
sunlight.
The arrow is pointing to
where the orange burner
would have been.
Data Analysis
Figure 5: Comparing two groups of balloons.
Interpret your graph. (This will help you
in your conclusion. Write three things
that you notice about the graph.)
This graph shows.......
The rectangular prism shaped balloon
had much better results than ours.
Our balloon is about 1/4 the hang time
of theirs.
Our column is much smaller than
theirs.
This graph also shows that our average
is much lower than their average.
There is a 17.7 second difference
between the two balloons.
Conclusion/Discussion
As you continue through the years, the conclusion and discussion will be written in paragraph form.
However, at this point we will break it up into smaller chunks. Answer the following questions in detail. Do
your best to answer all of the questions.
1. What was your hypothesis AND was your hypothesis supported?
Our hypothesis was that if we made a hot air balloon with a bullet tip than it will have a greater hang time
than a hot air balloon made into a cube because the hot air will be contained at the point of the hot air
balloon. Our hypothesis was not supported.
2. Support your answer to the question above with experimental observations. (You must use data! Use
numbers!)
Our hypothesis was not supported because in the final results, the cube had an average hang time of 24
seconds and our balloon with the pointed end had an average of 6.333333333 seconds. That is why our
hypothesis was not supported.
Conclusion/Discussion (continued)
3. Explain why you think you got the results you did?
I think we got the results we did because in our design of the balloon, there was lots of overlapping paper.
And, at the beginning of the testing, we had a full open bottom, so it couldnʼt trap as much hot air as if it had
closed end. Also, there wasnʼt much weight at the bottom of the balloon so it flipped over easily.
4. Give at least two likely experimental errors (include which specific observation it was, what you think the
error was, and why you think you made that error. “This is what I saw? This is what the error was... This is
why it happened?)
I saw that when Graceʼs, Sophiaʼs, and Laurenʼs hot air balloon got up over the balcony where we were
testing, we had to push it back out so that the test could continue. the error was, when you push on the
balloon, you are really pushing hot air out because you are diminishing the volume. Thus, making it float
down, and also if you pushed too hard you might cause it to rip. It happened because we had already had
the balloon float up and over the balcony so we decided to push it back out, I think that we might have
pushed too hard.
5. If you did this experiment again, how would you improve this experiment? (explain in detail)
If I did this experiment again, I would improve it by taking more time to finish the hot air balloons. I felt like
we were somewhat rushed with time, and I would like to make sure everything is ok and that we did
everything right before we go out testing the balloon.
6. What further experiment would you want to try? (explain in detail, include a brief picture of the
experimental setup)
A further experiment I would like to try is would the colors change the hang time of the hot air balloons. I
would like to try this because I have heard that some colors absorb heat and others donʼt. I have heard that
black absorbs and white reflects so we could test these colors. We would test this by doing a test with a
black hot air balloon and a white hot air balloon, both of the same shape, size and design. That way, we
could refer back to this test and say whether the results were changed by color or not. And then if needed,
we could go back and do this whole test again.