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Grade 7


Module 5

Launching the rocket

Assignment 1:

Options for launching the rocket

[lo 1.11]

Option 1

  • Use a stiletto or a sharp object, like a pair of compasses, to pierce a small hole through the length of a cork. Push the wide end of the air valve into the plastic tube. Push the other end of the air valve through the opening in the cork. You can try in a similar way to affix the air valve to the bottle-top. Half-fill the bottle with water .The water is the “propellant”. The compressed air above the water will provide the energy to force the rocket forward. Hold the intact bottle and push the cork with the air valve into the opening of the bottle. Push it in properly so that the cork cannot slip out of the opening. (You could rub some petroleum jelly [ Vaseline ] onto the cork, so that it will slip out easily during the launching.)

Option 1

Attach the other section of the plastic tube to a bicycle pump. Turn the rocket so that the right side points upwards. Make it stand upright on the base. You are now ready to launch your rocket. Find a flat launching platform away from trees and buildings. Make the rocket stand firmly on its tail fins and have everybody stand at a distance (± 5 m). Start pumping. Air bubbles will rise through the water. When the pressure inside the bottle is high, the cork and the water will be forced out at the opening and the rocket will shoot into the air. Be careful not to bend over the rocket. Only the teacher and the learner involved should stand next to the rocket.

Option 2

For the teacher:

The launching device provides a safer option. The rocket can be launched vertically from it and the device also keeps the rocket from falling over. It is, however, necessary for you to build this launching device. You also have to test the device beforehand. (The launching fins then do not really serve their purpose.)

Option 2

Launching device

Launching instructions :

  • Find a flat surface outside, away from trees and buildings.
  • Half-fill the bottle with water.
  • Turn the launching device at an angle and move the mouth of the rocket (opening of the bottle with water) over the wheel valve. Press the Perspex sheet round the neck of the bottle so that it will help the rocket to stand upright.
  • Pump air into the bottle with a foot pump not exceeding 40 psi.
  • Stand back ± 5 m and pull the Perspex sheet out.
  • The rocket should shoot vertically into the air. Do not allow learners to crowd around the rocket while it is being launched. Keep onlookers at a safe distance.

Assignment 2:

To calculate how high a rocket can fly

[lo 1.13]

Do you know that you could use a mathematical formula and scientific pocket calculator to calculate how high your rocket has travelled? How? Calculate the angle at which the rocket has soared.

Mathematical calculation: tan<A x adjacent distance = height

e.g. tan 75º x 4 m =

Try to launch your rocket three times and record your observations in the column line linear graph below:


Assignment 3:

[lo 1.12]

Evaluate the appearance of your rocket after the first flight/launch with reference to the questionnaire below by putting a tick in the appropriate column next to the corresponding question. Try to make the improvements/changes if necessary to ensure more height during the 2 nd and 3 rd launches.

Yes, definitely Yes Uncertain No
1. Is the conical point straight? (If it is skew, it will cause unequal airflow from the point to the tail, which will result in more resistance.)
2. Is there a smooth joint between the conical point and the body of the rocket? (If the diameter of the conical point is larger than the body, it will cause the airflow to be irregular, which will increase the air resistance.)
3. Is the body of the rocket nice and smooth? (Any surface of the rocket, which is not smooth, will increase air resistance.)
4. Are the fins mounted straight and firmly? (Skew launching fins could hamper the launching of the rocket and could cause the rocket to be skew during flight.)
5. Are all the launching fins of the same size and are all the other fins also of the same size and do they have smooth edges? (Fins of different shapes and sizes cause more air resistance.)
6. Has the finishing been done very well and is the rocket sturdy? (A rocket that is not sturdy and properly finished off, also increases the air resistance.)


Learning outcomes(LOs)
LO 1
Technological processes and skillsThe learner will be able to apply technological processes and skills ethically and responsibly using appropriate information and communication technology.
Assessment standards(ASs)
We know this when the learner:
Evaluates :1.12 evaluates the product or system based on criteria linked directly to the design brief and some of the specifications and constraints, and suggests improvements or modifications;
1.13 evaluates the efficiency of the plan of action followed and suggests improving future plans;
Communicates :1.14 presents ideas (in a project portfolio) using two-dimensional or three-dimensional sketches, circuit diagrams or system diagrams.


Assignment 1

Learners can help each other to carry out option 1. A maximum altitude is the main objective at each launching. The learners and the teacher can observe which rockets achieve a maximum altitude, e.g. ± 70m, and which as less effective.

Assignment 2

The teacher can deduce from the learners’ mathematical computations whether the learners are able to calculate the altitude reached by their rockets. Each learner’s line graph and flight trajectory will differ.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Technology grade 7. OpenStax CNX. Sep 10, 2009 Download for free at http://cnx.org/content/col11032/1.1
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