We’re all a bit space mad at the moment so took a quiet moment this half term to make some straw rockets with a twist.
- Wide straw
- Normal Straw
- Paper clips
- Felt tip pens
Cut the wider straw so you have a segment about one third the length of your normal width straw.
Completely seal one end of the wide straw with sellotape so no air can pass through it. Check this by blowing down the straw, does any air escape?
Draw a picture of a rocket or other space object on a piece of paper and use sellotape ( double sided works best ) to attach to the wider straw.
Place the wider straw onto one end of the normal straw and blow!
Watch your rocket fly!
Try pointing the straw at different angles and blowing harder/less hard to see how the flight of the rocket changes.
Why does this happen?
When you blow air down the straw it travels to the end and pushes its way out, taking the rocket straw segment with it as it moves. The harder you blow into the straw the more energy the air has and the further your rocket will fly!
Change the trajectory
What happens to your rocket if you point it straight up? How far does it fly? Does it fly differently if you point it horizontally?
There are two forces acting on the straw rocket. Gravity is pulling it down while the force from you blowing the straw is pushing it forward. These two forces combined give a curved movement. A real rocket needs to overcome the gravitational force downwards.
Add some weight to your straw rocket and see if that affects how far it travels, you could use cardboard instead of paper as the rocket or add paper clips!