Name _____________________
Date _____________
Class ____________________
Design and Build a Water Rocket
By designing a water rocket, students will experience the three-step design process: research and investigate,
design and build, and evaluate and redesign.
Skills Objectives: After this lab, students will be able to
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Design an experiment
Evaluate results against specified criteria
Troubleshoot problems that occur during the design and build stage
Materials
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large round balloon-provided
scissors
tap water
graduated cylinder
50 paper clips in a plastic bag
empty 2-liter soda bottle
poster board
modeling clay
tape
altitude tracker-see part 3
stopwatch
tire pump (one per class)-provided
water rocket launcher (one per class), provided
Problem: Can you design and build a rocket propelled by water and compressed air?
Procedure:
1. What is Newton’s third law?
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2. What does Newton’s third law have to do with how a rocket works?
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PART 1 Research and Investigate
1. Create a data table on a separate sheet of paper.
2. In an outdoor area approved by your teacher, blow up a large round balloon. Hold the balloon so that the
opening is pointing down. Release the balloon, and observe what happens. CAUTION: If you are
allergic to latex, do not handle the balloon.
3. Now place 50 mL of water in the balloon. Blow it up to the same size as the balloon in Step 2. Hold the
opening down, and release the balloon. Observe what happens.
4. Repeat Step 3 two more times,varying the amount of water each time. Write down your observations.
PART 2 Design and Build
5. You and a partner will design and build a water rocket using the materials provided by your teacher.
Your rocket must
o Be made from an empty 2-liter soda bottle
o Have fins and a removable nose cone
o Carry a load of 50 paper clips
o Use only air or a mixture of air and water as a propulsion system
o Remain in the air for at least 5 seconds
o Be able to be launched on the class rocket launcher
PART 3 Altitude Tracking: Students must go to the following website and construct the
altitude tracker prior to launching the rocket-one altitude tracker per group of 4 must be
completed and students must know how to use the tool to track the distance the rocket
reaches in the air.
http://exploration.grc.nasa.gov/education/rocket/TRCRocket/altitude_tracking2.html
PART 4 Evaluate and Redesign
6. Begin by thinking about how your rocket will work and how you would like it to look. Sketch your
design and make a list of materials that you will need.
7. Rockets often have a set of fins to stabilize them in flight. Consider the best shape for such fins, and
decide how many fins your rocket needs. Use poster board to make your fins.
8. Decide how to safely and securely carry a load of 50 paper clips in your rocket.
9. Based on what you learned in Part 1, decide how much, if any, water to pour into your rocket.
10. After you obtain your teacher’s approval, build your rocket.
11. Test your rocket by launching it on the rocket launcher provided by your teacher. CAUTION: Make
sure that the rocket is launched vertically in a safe, open area that is at least 30 m across. All observers
should wear goggles and stand at least 8–10 m away from the rocket launcher. The rocket should be
pumped to a pressure of no more than 50 pounds per square inch.
12. Use a stopwatch to determine your rocket’s flight time (how long it stays in the air).
13. Record in a data table the results of your own launch.
14. Make any corrections or changes in your design and prepare for second launch. Record your data.
15. Compare your design and results with those of your classmates.
Launch #
Time to Peak (s)
Time from peak to
landing (s)
Post flight mass
(g)
#1
#2
Calculations: Complete the following calculations. Be sure to show all of your work, use the correct units
and round to the nearest hundredth.
1) Distance: using the altitude tracking meter created in part 3= _____________________
2) Average velocity: Formula: v = distance/ time to peak ________
3) Mass: Post-flight mass = ______________g = ___________________kg
4) Momentum:
Formula: Momentum = Post-flight mass x velocity
Analyze and Conclude
1. Observing: What did you observe about the motion of the balloon as more and more water was
added?____________________________________________________________________________________
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2. Drawing Conclusions: What purpose did adding the water to the balloon
serve?____________________________________________________________________________________
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3. Designing a Solution: How did your results in Part 1 affect your decision about how much water, if any, to
add to your rocket?
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4. Evaluating the Design: Did your rocket meet all of the criteria listed in Step 5? Explain.
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5. Evaluating the Design: How did your rocket design compare to the rockets built by your classmates?
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Which rockets had the greatest flight time? ______________________________________________________
What design features resulted in the most successful launches? _______________________________________
6. Redesigning: Based on your launch results and your response to Question 5, explain how you could/did
improve your rocket. How did these changes help your rocket’s performance?
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7. Evaluating the Impact on Society Explain how an understanding of rocket propulsion has made space
travel possible.
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Communicate: Write a paragraph that describes how you designed and built your rocket. Include a labeled
sketch of your design.
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Sketch:
Water Bottle Rocket --Scoring Rubric
In evaluating how well you complete the water bottle rocket, your teacher will judge your work in four
categories. In each, a 4 is the best rating.
4
3
2
1
Planning
Student thoroughly
considers the forces that
would affect the rocket.
Sketch of the rocket is
useful and includes
measurements.
Student adequately
considers the forces
that would affect the
rocket. Sketch of the
vehicle is useful.
Student considers
some of the forces
that would affect the
rocket. Sketch of the
rocket is rough.
Student minimally
considers the forces
that would affect the
rocket. Sketch of the
rocket is not made.
Rocket
Building
Student follows all lab
procedure, and work
shows evidence of
having thoroughly
tested and modified the
rocket.
Student follows most
of the lab procedures,
and work shows
evidence of having
adequately tested and
modified the rocket.
Student follows some
of the lab procedures,
and work shows
evidence of having
tested or modified the
rocket.
Student did not follow
many of the
procedures, and work
shows little evidence
of having tested or
modified the rocket.
Lab write up is
thorough and well
organized. Student
Rocket lab
Presentation communicates all
appropriate features of
the rocket.
Presentation is
adequate. Student
communicates most of
the appropriate features
of the rocket.
Presentation is
appropriate but is hard
to follow. Student
communicates some
of the features of the
rocket.
Presentation is
inappropriate and hard
to follow. Student
communicates a few
features of the rocket.
Student works equally
Participation
with team member.
Student participates in Student participates in Student minimally
all aspects of team
some aspects of team participates in team
discussions.
discussions.
discussions.
Worksheets that accompany this lab will be graded separately for
completeness, accuracy and evidence of calculations (show your work)