Step 1: The problem is that i have to make the bottle light and it needs to be able to shoot off into the air high.

Step 2:Brainstorming

Step 3:Research: Water Rocket Ship 2.0

Drag - Drag is created by air resistance. Imagine running down a track with a small parachute attached to your back. You would notice that it is more difficult to run with the parachute pulling you back versus running with no parachute. The parachute, in this example, causes considerable drag. When a rocket flies through the air, drag pushes back - or resists the rocket's forward motion. A rocket's drag is affected by shape, texture, velocity, as well as other factors.

Lift - On a rocket, Lift is a side force used to stabilize and control the direction of flight. This is quite different from the concept of lift as it relates to an airplane. On an airplane, lift is a force that overcomes weight to enable flight. In the Rockets 2.0 application, we will simply discuss the concept of stability to avoid confusion.

Thrust - This is the force that produces lift-off, or upward movement of a rocket. Thrust is produced by engines or some other form of propulsion system. For lift-off to be achieved, thrust must exceed weight.

Weight - A combination of factors affect the weight of a rocket and can include cargo, passengers, fuel, parts of the rocket, materials, and other items. Weight is related to mass, but also includes the gravitational pull of the Earth.

  • The troposphere is the first layer of earth's atmosphere starting at sea level and rising up about eleven miles. Weather and clouds exist in the troposphere. In the troposphere, temperature decreases as altitude increases.
  • The stratosphere is the second layer of earth's atmosphere and continues from eleven miles up to 31 miles above sea level. The ozone layer is part of the stratosphere. The ozone layer absorbs most of the ultraviolet solar energy and that makes the ozone essential for our survival. Temperature increases with altitude in the stratosphere. Also, clouds exist in the lower levels of the stratosphere.
  • The mesosphere is the third layer to the earth's atmosphere and continues from 31 miles to 50 miles. The temperature in the mesosphere decreases as altitude increases.
  • The ionosphere is the fourth layer of earth's atmosphere and extends from about 50 miles to about 400 miles from sea level. Auroras (a natural light display in the sky) happen in this layer. Temperature in the ionosphere increases as altitude increases. In the ionosphere a layer known as the thermosphere starts. The name thermosphere comes from the temperature increasing as altitude increases.
  • The exosphere is the fifth layer of the earth's atmosphere. The exosphere is the outermost layer and begins at an altitude of about 400 miles and continues up to about 800 miles. The thermosphere stops in the exosphere and temperature decreases quickly after the thermosphere stops. The exosphere is sometimes referred to as the critical level of escape. An object traveling with enough velocity can escape through the exosphere into space.

All rockets will rotate about their center of gravity during flight. A stable rocket will be able to recover from this rotation and return to its normal flight path. This rotation is typically characterized as roll,pitch, or yaw.

  • Roll is a twisting motions about the roll (longitudinal) axis. Roll movement is not really a problem on a water rocket since it does not tend to alter the rocket's flight path.
  • Pitch refers to an up and down movement of the rocket's nose. This movement can take the rocket off of its intended flight path and could result from a gust of wind. Careful attention to the location of the center of gravity and center of pressure will ensure pitch stability.
  • Yaw refers to the side to side movement of the rocket's nose. This movement can take the rocket off of its intended flight path and could result from a gust of wind (very similar to pitch). Careful attention to the location of the center of gravity and center of pressure will ensure yaw stability.

Weight is one of the three forces on a rocket seen in the rocket image below. Weight is the force generated on the rocket by the gravitational attraction of the earth. It is the combined mass of the rocket itself, including the fuel, and the payload, multiplied by the gravitational pull from earth. As shown in the rocket image below, weight opposes thrust - one of the other forces of flight. Weight pulls vertically downward through the rocket's center of gravity (CG). Center of gravity will be explained in more detail in the stability section.

One of the elements of weight is the gravitational force from the earth. This gravitational force is fundamentally different from the aerodynamic forces of lift and drag. Lift and drag are mechanical forces, meaning the rocket has to be in physical contact with the air to generate the force. However, a gravitational force is a field force. A field force means that two objects do not need to be in physical contact to generate a force between them. The earth does not need to be in physical contact with the rocket to generate the gravitational force. Isaac Newton expressed the relationship between weight, mass, and gravitational pull in a single equation:

weight = mass x gravity

Rocket Stability

It is important for a rocket to have and maintain stable flight. In order to maintain stable flight, rotation around all three axes - especially yaw and pitch - must be prevented. The reason controlling rotation is more important around the yaw and pitch axes is because instabiliy about these axes would change the intended flight path. If the rocket was to rotate around the roll axis the flight path would not necessarily change. In order to understand rocket stability you must first learn about two very important points on the rocket. These two points are the center of gravity (CG) and center of pressure (CP).

Step 4:

Step:5: My first rocket that I had the parachute did not deploy. Then the second rocket the parachute worked but it was too heavy. So the last one I made was the lightest and the best and I also made the nose longer.

Step 6:

Step 7:

Step 8:

Comment Stream