# Principles of Rocketry

## Presentation on theme: "Principles of Rocketry"— Presentation transcript:

Principles of Rocketry

Our Water Rockets Instead of hot gases 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 Don’t WRITE This

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 g 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. The 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 DON’T WRITE THIS DOWN

Stability During Flight….
Think about a dart…. DON’T WRITE THIS DOWN Fins or feathers in the rear act like wind veins and trail behind Heavy mass in front carries the momentum

Newton's 3 Laws Explains Everything
WRITE THIS 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 and opposite reaction.

Center of Gravity

The next drawing indicates how the fin should look once folded.
Mark straight lines on the bottle by putting the bottle in the door frame or a right angle and trace a line on the bottle with a marker. Use these lines as guides to place the fins on the bottles.

Title: Rocket Lab Purpose: Hypothesis: Procedure: Drawing: Rocket Design Rough Draft (label all parts, give dimensions, shape, etc.)