Friction due to fluid ( gases or liquids) Drag - Friction due to fluid ( gases or liquids) Poor taping creates turbulence on rocket surface.

Aerodynamics – 1. Study of the forces acting on objects in motion in fluids.

Streamline – 1. An object shaped to make air flow smoothly around it

Inertia – 1. An object wants to keep doing what it is already doing unless a force acts on it. ( Due to mass) 2. The rocket needs mass to help it continue to travel upward.

  Inertia Correct amount of Mass Incorrect amount of Mass Inertia is the tendency of an object to resist any change in motion. It is associated with the mass of an object.   A bottle rocket that is HEAVIER has MORE Inertia, because it has MORE mass. MORE Inertia will offer GREATER resistance to a change in direction. Therefore the wind will have LESS effect on a bottle with MORE INERTIA. A LIGHTER bottle rocket has LESS inertia, because it has LESS mass. LESS inertia means the rocket will have LESS resistance to change in direction. Consequently, the wind has a GREATER effect on the rocket’s path of motion. Correct amount of Mass Incorrect amount of Mass

 BALLAST: any mass added to a vehicle to improve STABILITY and increase INERTIA. Wind Direction  Air Resistance (DRAG) Ballast Center of Mass Stability: Ballast towards the nose cone will shift the center of mass forward. Inertia: More weight (ballast) increases inertia and will prevent a bottle’s path of motion (or Trajectory) from being prematurely overcome by DRAG & WIND FORCES........CAREFUL! Too much Ballast will make the vehicle too heavy ( Newton’s 3rd Law).

Center of Mass / Gravity – 1. The exact point where the mass is balanced on the rocket. 2. A higher center of mass enables the rocket to have inertia to fly straight and upward in altitude.

Fin Specifics – 3-4 Fins evenly balanced for stability Fins should be small and light but still firmly attached.

** increase surface area with fins help create stability.

Rocket Fin Shapes More Aerodynamic fins: Thinner, more streamlined fins reduce drag. Position fins toward the tail of the rocket (moves CP!).

Nosecone Guidelines – Nose is lengthened for higher center of mass. Nose is filled with paper for stability and evenness of mass. Nose is a parabola shaped for reduced drag and aerodynamics

Maximum Mass - The mass of your rocket should not exceed 250 grams. Optimum mass is approximately 200 grams

Center of Lateral Area (CLA) - 1. The point along the rocket where the wind forces on either side are equal.