# Water Bottle Rockets Worksheet Welcome to Get SET by nikeborome

VIEWS: 226 PAGES: 3

• pg 1
```									Standards covered: Grade 8: Motion a-f: the velocity of an object is the rate of change of its position.
Forces a-g: Unbalanced forces cause changes in velocity.

Team Get S.E.T
Water Bottle Rockets
Purpose: To give students a hand on activity to demonstrate the basics
Of kinematics.

Learning Outcomes:
Upon completing this mini-course, students should be able to:
• Understand and apply kinematics in real world situations
• Identify and explain Newton’s Laws
• Critically understand the concept of motion in 1-D & motion in 2-D
• Solve basic Kinematic problems with respect to forces and motion
• Recognize forces acting upon an object at any time, such as gravity, friction, etc.

Materials Needed:
1.    7 of 2 liter bottles
2.    Cardboard
3.    Paper
4.    Glue
5.    (7) Scissors
6.    (1) Launcher
7.    Nuts/ bolts

Directions:

Rocket-building

1)     Obtain an empty two-liter bottle (soda bottle or other similarly-necked bottles).
2)     Design and cut fins out of desired material.
3)     Glue the fins with the neck of the bottle pointing towards the ground as this is the bottom of the
rocket. Position the fins to theoretically offer the best performance.
4)     Using the nuts/bolts provided, decide how many to use to add weight and stability. Glue or tape
the weights together. Then glue the single weighted mass to the bottom of the bottle. Be sure to
evenly distribute the weight for optimal stability.
5)     Form the nosecone out of the desired material. Check to see that it fits on the bottom of the
bottle. Adjust or redesign if necessary.
6)     Place nosecone firmly onto the bottle. While drying, position the bottle so that the nose cone is
facing downwards and prop it up. This will allow excess glue to seep into the cracks and strengthen
the adhesion as well as prevent glue from running down the sides of the bottle.
7)     Decorate the rocket after the fins and nosecone have finished drying.
Standards covered: Grade 8: Motion a-f: the velocity of an object is the rate of change of its position.
Forces a-g: Unbalanced forces cause changes in velocity.

Launch

1) IMPORTANT: Bystanders should keep a safe distance from the launch site (15-foot radius). Make
sure no hazards such as electrical power lines, trees, and building are near launch site. Only launch if
there is little to no wind and visibility is good.
2) Fill the rocket with water to desired level. Different water levels will affect the maximum altitude of
the rocket.
3) Quickly place the bottle onto the launcher so as to minimize water loss. If water loss is inevitable, fill
the bottle with a little more water than desired to compensate for leakage/spillage.
4) Once the rocket is firmly seated onto the launcher, insert the retaining pin through the holes on the
side of the launcher. MAKE SURE THAT THE PIN PASSES OVER THE RIM OF THE NECK AND IS
SECURELY HELD IN PLACE.
5) Pump to pressurize the rocket. DO NOT EXCEED 40 PSI, BOTTLE MAY RUPTURE.
6) Before launching, retreat AT LEAST 15 feet. Make sure the launch area is safe and clear of
bystanders. Verbally announce a countdown before launching.
7) To launch pull the string that is connected to the retaining pin.
8) Experiment with different water and pressure levels to obtain the maximum altitude for your rocket.

Questions/Problems:
1) Explain how the launch of a rocket illustrates each of Newton’s three laws of motion:

2) Find the highest point of the rocket:
a. if its initial speed is 94m/s
b. if it was in the air for 40 seconds
Standards covered: Grade 8: Motion a-f: the velocity of an object is the rate of change of its position.
Forces a-g: Unbalanced forces cause changes in velocity.

3) A model rocket is launched from rest and its engine delivers a constant acceleration of 10m/s2
for 4.0s after which the fuel is used up. Assuming the rocket was launched straight up into the
air and ignoring air resistance,
a. Find the maximum altitude of the rocket.
b. Find the total time the rocket is airborne.

4) A 2000 kg rock generates a 2.0 X 10^5 thrust. What is the rocket's initial acceleration upwards?
Given: Mass of rocket = 2000 kg

Gravity = 9.8 m/s^2

Thrust = 2.0 X 10^5 N

5) In the last problem, we found the acceleration of a rocket launched straight up. Now, what
would be the max height the rocket reaches if the engine lasts 5.0 seconds before burning out?
Draw a diagram if needed. [Hint: You have acceleration, now use kinematic equation Y(final) =
Y(initial) + V(initial)T + .5 X a(T^2).)
Given:
acceleration = ____

T time = 5.0 s

V velocity(initial) = 0.0 m/s^2 [Since the rocket is moving at constant speed]

Y height = _____

```
To top