Principles of Rocketry

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)

DRAW THE ROCKET AND WRITE EVERYTHING DOWN Water Rockets Work Like Real Rockets DRAW THE ROCKET AND WRITE EVERYTHING DOWN 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

How Newton's Laws Affect Our Rockets WRITE THIS Newton's First Law The pressure inside the rocket must overcome the INERTIA of the rocket’s weight to launch. If the rocket has too much water, it will have too much weight/INERTIA.

a = F m Newton's Second Law This is why you need just the right mass and force to achieve a good acceleration 80psi is perfect for 275-350g a = F m

DON’T WRITE WHAT’S IN YELLOW 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 (action force), so your rocket must go up (reaction force).

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

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

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

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

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

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

DON’T WRITE WHAT’S IN YELLOW 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 DON’T WRITE THIS Newton's 3 Laws of Motion #1An object will stay at rest unless a force acts upon it. #2Force = Mass x Acceleration #3For every action there is an equal an opposite reaction.

Center of Gravity

Bring These Materials to class on Monday Two, 2-Liter soda bottles Old cd’s Duct Tape Manila envelopes Clay Stickers, paint, colorful duct tape for prettiness and other decorations are optional

Lesson by Mr. Alex Sowyrda Cooperating Teacher: Mr Lesson by Mr. Alex Sowyrda Cooperating Teacher: Mr. Robert Jones Kenney Middle School 7th Grade Technology Hannibal, NY Sept – Oct 2004 http://www.hannibal.cnyric.org/TeacherWebs/Rjones/rockets/PowerPoint/Rocketry_files/frame.htm