BUILD YOUR OWN ROCKET, LAUNCH YOUR OWN ROCKET, POST YOUR BEST LAUNCH ON THE INTERNET & TAG US ON SOCIAL MEDIA (Twitter, Facebook) @DundeeSciCentre #DundeeSciCentre Pump air in with a bike pump and increase the air pressure inside the bottle. Finally, the pressure is high enough for the rocket to take off, firing water out of its mouth and streaking up into the sky. This rocket can go 10-20 meters off the ground. It’s serious. You should only launch your rocket under adult supervision and never put any part of your body above it when you are pumping it up.
You need:
A plastic (PET) bottle (empty soft drink bottle – any size) A bike pump A needle to pump up a basketball OR a bike valve (cut it from an old bike tyre). A rubber stopper (that fits the mouth of the bottle) Tie wire or coat hanger wire (OR thick cardboard) Straw Strong sticky tape Pliers, Wire cutter Water
There are two types of launch pads you can make:
Type 1)
Type 2)
What to do Make your rocket launch pad: This is the trickiest part. You need to make something sturdy enough to keep the rocket standing up straight, about 5 – 10cm off the ground. The fins or the stand must hold the rocket high enough off the ground for the pump to attach underneath.
Type 1: fold a wire into a stand. OR make a stand out of an upside down ice cream bucket with a hole in the top for the bottle. (These stands stay on the ground while the bottle flies up.) Type 2: Use cardboard cut outs of fins, attached to the bottle with sticky tape. (The fins will travel up with the rocket when it launches.) Make your stopper: You will need to make a stopper which will allow you to pump air into the rocket until it blasts off. There are two easy designs below. You will need an adult to help you build these.
a)
b)
To set your rocket up 1. 2.
Fill the bottle about one third full of water. Push the rubber stopper into the mouth of the bottle firmly.
3. 4.
There are two ways to attach the pump: a. Drill a hole through the stopper, and glue a bike valve over the hole. OR b. Poke the bike pump needle through the rubber stopper. It must be a tight fit. Place your bottle-rocket the right way up on its stand (with the bottle upside down)!
To launch your rocket 1. 2.
Pump air into the bottle. Keep pumping. Sooner or later the rocket will take off! (You get no warning. Don’t EVER lean over the rocket!).
Why it works Air fills the bottle-rocket as you pump. As you squash more and more air into the bottle the pressure increases. Eventually the air pressure will be strong enough to push the rubber stopper out. When the rubber stopper is forced out, the air pushes the water out too. As the rubber, water and air come out the bottom of the bottle, the bottle is pushed in the opposite direction. When the rubber-water-air-mix goes down, the bottle-rocket goes up! Because the bottle-rocket doesn’t weigh very much it goes a long way up. We put water in the bottle because water is much heavier than air. So the rocket will go further.