Car Rocket Experiment
Our group decided to do a car rocket experiment. This experiment involves launching a
car while releasing the air from a balloon that is attached to the top of the car. Eventually we
looked at the distance formula and kinetic energy formula in order to see how much energy
needs to be released from balloon so our car could move at different distances. Our car rocket
experiment is based on a real rocket thrust. Thrust is the force that actually moves the rocket
throughout the air. Thrust is made by something called the propulsion system. (nasa.gov) The
amount of work that is put into the rocket eventually creates the reaction of acceleration which
produces the thrust onto the engine of a rocket.
Just like in a real rocket. Our rocket consisted of a balloon attached to the hood of the
car. The air in the balloon acted like the thrust force because when more air was blown into
the balloon our car traveled at a farther distance. Obviously when less air was blown into the
balloon the car traveled at a smaller distance.
Ultimately our experiment was about how a rocket thrust works, but we also got the
chance to incorporate the distance formula as well as the kinetic energy formula into our
experiment. It would have been great to incorporate the real thrust formula which is shown in
the picture above, but our experiment was a little less complicated than an actual rocket.
http://exploration.grc.nasa.gov/education/rocket/rktth1.html
To do this experiment, you will need:
-balloon
-car
-ruler
-string
-tape
-straw
-stop watch (phone)
Procedure
1. Tape the straw to the car.
2. Place the straw through the string.
3. One person should be holding one end of the string and another person will be holding
the opposite side of the string.
4. Now you have to perform 3 different trials of distance with 3 different sizes of the
balloon.
5. Blow the balloon up, but don’t tie the end (hold it with your fingers)
6. Measure the balloon’s size in inches.
7. You will need to attach the balloon to the car, so first place the tape onto the balloon and
then tape the balloon to the car. (make sure the balloon won’t fly away)
8. Make sure that both ends of the string are held tightly and let the balloon go, but while
doing this make sure someone is timing the car movement.
9. After the balloon is released you want to measure the distance and put the distance and
time into a table.
10. Perform three trials at different balloon sizes.
11. Put all your data into a table.
12. You will now have to convert your measurements in order to find the velocity and kinetic
energy. (inches to meters)
13. You will need to know the mass of the car which is 107g
14. When all your measurements are converted you will have to use the Distance formula to
find the velocity V=d/t
15. Once you have your velocity place that into the table as well.
16. Next you will need to find the kinetic energy by using this equation KE=1/2mv^2
17. Place the kinetic Energy into the table
18. Make a graph to show your findings.
19. Now you can see the relationship between the amount of energy released and the distance
traveled.
Both our group and two other groups in the class performed our experiment. The point of our
experiment was to demonstrate thrust using a balloon as the source of power. The point of the
experiment was to answer the following questions.
1. How much energy does it take for the car to travel the distance is it went in each of the
three tests?
-In order to answer this question each group had to use the formula d=v/t to determine the
velocity.
2. What is the kinetic energy the car put out for each of the three tests?
-In order to answer this question each group had to use the kinetic energy formula
KE=1/2mv^2.
3. What conclusion can you make from the graph you made with regards to how energy and
velocity are related?
-This question would vary for each group depending on there data they acquired during
there trials.
Overall our experiment appeared to be one each group enjoyed and helped everyone
better understand thrusting.
Our Data:
Ballon Size
6 inch
8 Inch
10 Inch
Distance Traveled
12 inch
45 inch
72 inch
Amount of Time
1.2 seconds
2.0 seconds
2.8 seconds
Velocity
.254 m/s
.57 m/s
.65 m/s
Kinetic Energy
0.0034
0.0173
0.0226