Squeeze Bottle Rocket It's easy to turn a juice bottle into a rocket launcher. email to friend
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It's easy to turn a juice bottle into a rocket launcher. How? Grab a few straws, some modeling clay and an empty juice bottle to make a launcher that will send the straw rocket soaring across the room. Ok, you'll learn something about Newton's Third Law of Motion at the same time.

This experiment was designed using the Kool-Aid Bursts juice product. While other flexible juice bottles may work, the Kool-Aid product works very well. The larger of the two straws should fix loosely over the smaller straw. There should be no friction or resistance at all or the straw will not be able to launch. If you're tired of searching for straws, just stop by Starbucks® to enjoy a drink and pick up a few straws.

Materials

- Kool-Aid Burst juice bottle (flexible plastic bottle)
- Modeling clay
- 2 straws - one large and one small. The larger diameter straw must be able to slip over the smaller straw. The large and small straws from Starbucks® work great.

Experiment
Video

Drink the juice! Clean and dry the bottle.
Push the smaller straw into the opening of the bottle. The straw should fit snuggly in the hole at the top of the bottle.
Use modeling clay to seal any possible leaks between the straw and the hole in the bottle. The clay will also make the straw more stable and less likely to wobble.
Push one end of the bigger straw into another piece of modeling clay. This "plug" will seal the end of the straw. Cover the plugged end with something soft like a Styrofoam packing peanut to keep the straw rocket from hurting anyone in case they accidentally get hit.
It's time to launch... Place the larger straw over the smaller straw. Ready, aim, squeeze! The larger straw launches off the smaller straw and the room erupts in a chorus of oohs & ahhhs!

How does it work?

While you're having fun launching straws, you're actually learning about Newton's Third Law of Motion. According to Newton, for every action there is an equal and opposite reaction. As you squeeze the bottle, air is forced out of the straw and pushes against the clay plug in the larger straw. The resulting force causes the straw to "launch" through the air.

Additional Info

Be careful! Never point the straw rocket at anyone. The goal here is to launch the rocket up in the air (not at someone). Be sure to cover the plugged end of the straw with something soft and round to protect someone from accidentally getting hurt by a sharp edge. Be creative! Once you've mastered the simple straw rocket, challenge your friends to a straw rocket design contest. Add a nose cone, some fins, a few decorations, and don't forget to name your straw rocket!