How to make a Bottle Rocket

Did you know you can make and launch a bottle rocket using just a plastic bottle, water, cork, needle adaptor and pump?

As you pump air through the water the pressure inside the bottle builds up until the force of the air pushing on the water is enough to force the cork out of the end of the bottle. The water rushes out of the bottle in one direction whilst the bottle pushes back in the other. This results in the bottle shooting upwards.

How to make a Bottle Rocket

How to make a Bottle rocket

What you need

  • an empty plastic bottle
  • cardboard made into a cone and  4 fins
  • a cork
  • a pump with a needle adaptor
  • water

How to make a Bottle Rocket

Instructions

  • Push the needle adaptor of the pump through the cork, it needs to go all the way through so you might have to trim the cork a little bit.

How to make a Bottle Rocket

  • Decorate the bottle with the cone and fins.
  • Fill the bottle one quarter full of water and push the cork in tightly.
  • Take the bottle outside  and connect the pump to the needle adaptor. Ours wouldn’t stand up on the fins so we rested it on a box, but if you make some strong fins it should stand up by itself.
  • Pump air into the bottle, making sure all spectators stand back, the bottle will lift off with force after a few seconds.

How to make a Bottle Rocket

Warning!

Please make sure an adult is around as the rocket takes off very suddenly and forcefully as you can see in this video clip. Do not approach the rocket once you have started pumping even if it looks like nothing is happening.

Why does the bottle rocket launch?

As you pump air into the bottle pressure builds up inside. If you keep pumping, the force of the air pushing on the water eventually becomes strong enough to force the cork out of the bottle allowing water to rush out in one direction while the the bottle pushes back in the other direction. This forces the rocket upwards.

Space rockets work in a similar way to the bottle, but instead of squirting water they burn fuel to make a powerful jet of hot gas. The force of the gas  downwards pushes the rocket upwards. This is a great demonstration of Newton’s Third Law.

How to make a Bottle Rocket

What is Newton’s Third Law?

Newton’s Third Law says:

‘for every action there is an equal and opposite reaction’

Who was Issac Newton?

Issac Newton was an English scientist most famous for his theory of gravity, but he also worked out three laws of motion to describe how objects move. You can find out more about the Three Laws of Motion in my book, This Is Rocket Science which has lots of activities to demonstrate all three laws based around rockets and space.

Extension Activities

Find out how to make a rocket mouse

Make a film canister rocket

Try one of these other easy air pressure experiments, including making a fake lung, a barometer and a coin popper!

Buy the book!

For more fun rocket science activities check out our new book This Is Rocket Science

This Is Rocket Science

How to make a Bottle Rocket

Affiliate links

Images taken from This Is Rocket Science


There are 78 comments

  1. Ticia

    That looks awesome. I learned the hard way not to go near projects like that after I did……. That was an unpleasant chemical burn and took a few days to stop stinging.

    I’ll have to see if we have a hand pump anywhere.

  2. Pauline

    WOAH! Look at that rocket go! Love this! I’ll be featuring this post as part of my Earth Day Activities for Kids: Upcycling roundup from the Weekly Kids Co-Op. xoxo P

  3. Whitney Coy

    SheKnows.com is excited to include a photo from Science Sparks on our site! In our article we will provide a link back to your blog post. Please contact us if you have any questions or if you would prefer that we not use your photo.

  4. retired

    There is a little air leaking out when flip the bottle over. Is there a certain cork or needle I can use? Right as the bottle fills up with air it starts to leak. any advice would be appreciated.

    Bob

  5. Britt

    Hi–what a fun craft! Would this work with different sized plastic bottles–such as a 16oz plastic soda bottle? Thanks!

  6. Charl

    I heart kitschy stuff. (ooh dang spelling error) I enjoy how quriky your tim horton pants are. Grr my brain is;&n39#t working otherwise I would totally have a more creative comment.

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