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Make a loop at the end of a 1 m piece of string.
Background
The aerodynamic forces at a rocket’s centre of pressure are centred. The centre of pressure is usually also close to the tail end of the rocket. The large surface of the fins and the smooth surface of the rest of the rocket cause it to be the position where the pressure is the same on both sides. To get the centre of pressure closer to the tail of the rocket, the front section (nose) of the rocket has a more pointed shape or the body section of the rocket could be made longer, because in that way it becomes more aerodynamic. By putting smaller fins on the front section of the rocket, the centre of pressure is moved closer to the front end.
R ules : The centre of gravity should be closer to the front end of the rocket than the centre of pressure. The centre of pressure should be the same distance or longer than the diameter of the rocket from the centre of gravity to the tail end. This will make the rocket stable and will help it to fly in a straight line.
Make a sketch of the side elevation of your rocket. Sketch the fins as well and draw as accurately as possible.
If you want to make any changes to your rocket to make it more stable, you can do it now. Decorate the bottles and fins so that it looks more like a rocket, for instance by painting it with an oil-based paint.
Now you are ready to launch your rocket.
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 - 3
Learners can help each other to find the centre of pressure and centre of gravity of every rocket. They will differ seeing that the appearance of each rocket should differ.
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