1. Rocket Science Forces and Streamlining

3. Before you start your mission you must first launch into space. But how do you do that? We all know that rockets have thrusters and rocket fuel, but how do they take off? Let’s recap the forces work you did in primary school…

4. Forces can affect objects in a number of ways. Forces can make an object: Stay still Start moving Stop moving Changedirection Deform Speed up Slow down

5. Like a child pushing open a door Forces can be both visible…

6. or a knockout punch Forces can be both visible…

7. or pulling on a rope Forces can be both visible…

8. Or forces can be invisible… Like the wind

9. Or Invisible… Like the forces felt by magnets

10. Or Invisible… Or the forces due to gravity, which makes things fall!

11. Every object on Earth has a downwards force due to gravity and we call this force Weight. The more mass an object has, the bigger it’s weight will be.

12. On Earth we always say that weight is acting towards the centre of our planet… Which is why Australians don’t just fall off Earth and float into space!

13. For our rocket to take off we must apply another force in the opposite direction (up). What do we call this force which acts upwards and where does it come from? It’s called thrust and it is caused by the jet engines! It will only take off if the thrust is bigger than the weight.

14. Now answer this question: Which car can travel the fastest? A B Correct A is the fastest, even if we put a supercharged engine in B it still wouldn’t win, But why?

15. An object which is designed to reduce air resistance (and therefore go faster) is said to be streamlined. So car A There is always a force that tries to stop you moving on earth which is called friction! You feel this as heat when you rub your hands together (try it) and it’s the reason that most things slow down. When an object is moving through air the frictional force is called ‘air resistance’. Thrust Air Resistance

17. They design rockets to be streamlined. ABCD Which rocket is designed to be the most streamlined?

18. EXPERIMENT TIME! Your mission is to design a test to see how streamlining effects a rocket taking off. You have the following equipment at your disposal…

19. Acetic Acid NaHCO 3 Bicarbonate of Soda Paper Vinegar Tissue paper Film canister (with lid) Pipette Spatula Sodium Hydrogen Carbonate Acetic Acid Scissors Sellotape

20. How good is your plan? Success Criteria SatisfactoryGoodExcellent 1. 2. 3. 4.