Here's what you'll need:
- An empty plastic bottle
- Cardboard made into a cone and 4 fins
- A cork
- A pump with a needle adapter
Now let's get started:
- Push the needle adapter of the pump through the cork and make sure it goes all the way through. To do this you may have to trim the cork down a little bit.
- Take your cardboard cone and fins and apply them to the bottle. (The cone at the top and the four fins at the bottom, so that the bottle resembles a rocket.)
- Fill the bottle with water until it's about a quarter full and then push the cork in tightly.
- Attach the pump to the needle adapter. If your bottle rocket won't stand up on it's own with the fins you made, rest it on a table, but if you make strong fins, you should fine and your bottle should stand up on its own.
- Pump air into the bottle and prepare for lift off! Make sure that everyone is standing away from the bottle as it will go up in the air with force after just a few seconds.
So what about the science? Check out Science Spark's explanation.