Water Rockets, for Parents and Kids

Rockets are very general. Anything that squirts some exhaust out the back is a rocket. For a chemical rocket, that exhaust needs its own fuel and oxidizer. For a water rocket, that exhaust needs a bicycle pump, a bottle, and some water, along with some sweat pumping up the compressed air.  1.Water bottles can easily be made into air pressure powered air or water rockets. To get a lower pressure launch, one kit will give you corks or bungs that pop out when the pressure gets high enough. To get controlled higher air pressure, other kits will provide a PVC pipe launch tube, with tire pump nozzles, and corks.  These launch tubes take more effort to build than the bottle rocket. 2.Huge space chemical rockets have the same rocket thrust concept as water bottle rockets, except liquid fuels and oxidizer are used like very cold hydrogen and oxygen.  Solid fuel is also sometimes used as a first stage booster, when the launch needs a large thrust and does not need to throttle.    Part 1: Rocket types: Rocket types, launcher kits, and water usesThe first part of the book, chapters 1-3, briefly compares the three different types of rockets - water bottle, toy chemical, and real space rockets - with their different speeds and altitudes, different fuels and energy sources. Bottle rockets have pressurized air, and toy and space rockets have solid fuel where fuel is pre-mixed with oxidizer, and liquid fuel. Part 2: Details of Bottle Rocket: Building and optimizing a bottle rocket The second part of the book, chapters 4-10, describes the air and water bottle rocket in more detail.  Topics are how to build and launch the bottle rocket, how to build the PVC launch tube or just buy a water rocket kit. 1.Air pressure Water bottle rockets provide a lot of hands-on building, and show how different size exhaust nozzles (diameter of hole in screw caps) impacts the force lifting the rocket.  Part 3: Appendices: Appendices A-C: Teacher and Parent ideas. A review of different launch pads for water rockets, and some ideas for activities to learn about rockets, and instructions for building your own plastic tube launch pad. Appendices D-J: All the thrust equations, if you want to estimate performance of your rocket. The third part of the book, the appendices, lists the equations to make predictions for the water rocket, or any rocket for that matter.