Principles of Rocketry

Bring These Materials to class on Monday 9/30/13 1 2-Liter soda bottle Duct Tape Manila envelopes or cardboard Stickers, paint, colorful duct tape for unique designs and other decorations are optional

Isaac Newton's 3rd law of Motion For every action there is an equal and opposite reaction                                                                                                                                              

What is the Action? Solid Fuel Rockets Fuel in solid form burns and is converted to hot gasses Hot gasses expand and create high pressure Pressure escapes out nozzle, pushing against air and rocket body equally - Reaction: Rocket moves forward, as gasses move backwards

Gasses Rocket Pascal’s Principle Action Reaction Equal pressure in all directions Pascal’s Principle Hot gasses escaping DRAW THE ROCKET Nozzle Burning fuel Producing hot gasses Solid Fuel

Space Shuttle: Solid and Liquid Fuel Rockets Liquid Fuel and Oxygen tank Feeding Engines Solid Fuel Rocket Boosters

Our Water Rockets Instead of hot gasses creating pressure, we use a bike pump and store pressure Action: Expelling water from engine bottle. (water is forced down) Reaction: Water resisting against rocket body. (Rocket is forced up)

Water Rockets Work Like Real Rockets Pascal’s Principle Reaction: Bottle forced up by water being expelled down High Air pressure is transmitted equally in all directions and parts of the fluid. Action: Water forced out and down by air pressure

Other factors that make the Water Bottle Rocket Fly Compressed Air + Water WRITE WRITE WRITE

Mother Nature doesn't like it when things aren't equal! When you pull the pin on the launch pad, and the latch holding your rocket to the launch pad pulls back, no force will be holding that rocket down! The unbalanced force of the High air pressure inside of your rocket will instantly rush out of the rocket nozzle pushing your rocket into the sky!

Newton's 3 Laws Explains Everything Newton's 3 Laws of Motion #1 An object will stay at rest unless a force acts upon it. #2 Force = Mass x Acceleration #3 For every action there is an equal an opposite reaction.

How Newton's Laws Affect Our Rockets Newton's First Law When you pressurize your rocket and compress all of that air into your rocket engine, the force of the launch pad latch equals the force of the compressed air. Your rocket is resting, it will go nowhere.

Newton's Second Law This law tells you how much force (push) is going to come out of your rocket nozzle. The air is the accelerant, the water is the mass. You are limited to a 2000 ml volume rocket engine (a 2 liter pop bottle).What ratio of compressed air (limited to 65 psi) and water (your choice) will produce the most force? About half the bottle full of water 100mLs Too much mass = too much inertia No mass = nothing to push off of

Newton's Third Law When you pull the pin, that area of High Air Pressure in the top of your rocket engine is going to force, throw, hurl, spew that "massive" water out the bottom of your rocket at a great speed. That water and air is pushing down, so your rocket must go up.

Stability During Flight The orientation of fins and distribution of mass help make the rocket stable. Center of Gravity Center of Pressure

Center of Gravity

Stability During Flight…. Think about a dart…. Fins or feathers in the rear act like wind veins and trail behind Heavy mass in front carries the momentum

David L. Pop Bottle Rocket video

Bring These Materials to class on Monday 9/30/13 1 2-Liter soda bottle Duct Tape Manila envelopes or cardboard Stickers, paint, colorful duct tape for unique designs and other decorations are optional