Transcript Water rocket Construction

Water Rocket Mission
Your mission: To successfully launch a rocket with a payload and retrieve
the payload without injury
Possible Materials

2-liter soft drink bottle

food trays

Poster board

Cardboard

Masking

4 ounces of clay

Safety goggles

Plastic grocery sacks or thin fabric scraps

String

Sandpaper or emery boards

Your payload is a raw egg
Background
A water rocket is a chamber, usually a 2-liter soft drink
bottle, partially filled with water. Air is forced inside with
a pump. When the rocket is released, the pressurized
air forces water out the nozzle (pour spout). The bottle
launches itself in the opposite direction. The bottle
usually has a nose cone for streamlining and fins for
stability.
KWL
 This is a team effort, so you must first figure out what
your team knows already to make a launch
 Use the Butcher paper to list all the things you think you
know about rockets—what makes them launch, what
physics do you already know to help. Do your partners
agree?
 What are you unsure of that might help you find out?
Things to think about as you
design
 Like all rockets, the flight performance of water bottle
rockets is strongly influenced by the rocket’s design
and the care taken in its construction. Beveling the
leading and trailing edges of fins allows them to slice
through the air more cleanly. Straight-mounted fins
produce little friction or drag with the air. A small
amount of ballast weight inside the nose cone helps
balance the rocket.
Plan your construction
Do you need some way to hold your rocket as you
construct it? How can you add fins and nose cone?
What size should they be? How much ballast should
you have in your nosecone? What can you use as a
recovery system? (parachute?)
Criteria for experimental design to
build a better rocket
1. Written Design with dimensions and drawings
2. Must have a parachute or retrieval system
3. Must have a way to carry your payload
Before launch you must test your
rocket
When the rockets have been completed, you will qualify
your rockets for flight by conducting string tests. Using
several feet of string, tie the rocket around the middle
so that it balances. Because of the nose cone weight,
the balance point will be towards the nose. When the
rocket hangs level, a small piece of tape should be
temporarily fixed to the string and bottle to keep the
string from slipping. The rocket is then twirled in a
circle. If the rocket tumbles while circling, it is not stable
and needs more nose cone weight, bigger fins, or a
combination of both. If the rocket circles with the nose
always pointed forward, it is stable and ready for flight.
Design
You must have a completed design by the end of
today. Your design must be written down with a
list of materials, a schematic drawing of your
rocket and a written plan of sizes and
dimensions. If you want you can pick up
supplies today and put them in a bag and label
your group and period number. You are
welcome to add to the supplies with material
from home but realize you will need to have
them here next class period.
We will Test flight on Wed. for A
days and Thursday for B days
 If your payload was unsuccessful—you may change
one variable and one variable only to make your
second attempt successful.
 If your payload was successfully retrieved change one
variable to see if you can get your rocket to go further.
Final Paper-one per group
1. Design must be written down with a list of materials, a
schematic drawing of your rocket and a written plan of
sizes and dimensions
2. Explanation of variable and why you chose it. Hypothesis
(what you thought would happen with the variable and
why)
3. Results and Data. What happened?
4. Analysis of data. Why did it happen?
5. Conclusion: Explanation of the bigger picture. What did
your investigation explain about rocketry and what
concepts might we study in physics that would relate to
rockets.