Name: Tai Le
Class: Intro to Digital Technology
Date: June 2, 2008
Water Rocket Research Findings
Vocabulary Terms: Use NASA’s journey into rocketry website (http://exploration.grc.nasa.gov/education/rocket/BottleRocket/journey.htm) to find the definitions of each of the terms below. Please write in complete sentences.
Stability :
The capacity of a vessel to return to its original position after having been displaced by external forces. The stability of a vessel depends on the meta-centric height.
Center of mass :
The average location of the weight of the rocket. The mass and weight are distributed throughout the rocket, and for some problems, it is important to know the distribution.
Center of pressure :
The aerodynamic forces act through a single point.
Lift :
Lift depends on the density of the air, the square of the velocity, the air's viscosity and compressibility, the surface area over which the air flows, the shape of the body, and the body's inclination to the flow.
Drag
“The acceleration of an object is directly proportional to the net force and inversely proportional to its mass.” This can be expressed in equation form:
Thrust
Thrust is the force which moves the rocket through the air, and through space.
Newton’s 2nd Law
“The acceleration of an object is directly proportional to the net force and inversely proportional to its mass.” This can be expressed in equation form:
Force = (Mass) x (Acceleration)
Newton’s 3rd Law
“For every action there is an equal and opposite reaction.”
Momentum
The product of mass and velocity, a quantity or measure of motion that is conserved in physical systems where no external forces are acting. For example, a body of moving air can only lose speed or change direction by transferring momentum to its surroundings (other air masses, landforms, vegetation, and so on).
Nozzle
A rocket engine uses a nozzle to accelerate hot exhaust to produce thrust as described by Newton's third law of motion. A nozzle is a relatively simple device, just a specially shaped tube through which hot gases flow.
Propulsion
The action of pushing or driving, usually forward or onward.
Weight
Weight is the force generated by the gravitational attraction on the rocket.
Questions: Answer a minimum of 2 of the 3 questions below writing in complete sentences and in your own words (don’t just copy text from the website).
Note: answer all 3 questions correctly for 25 bonus points
1. What are the main ways to create a stable rocket?
A rocket demands that it have these three features to create a stable rocket.
1. The nose cone.
2. The fairing (a ‘skirt’ that goes around the nozzle).
3. The fins.
These features keep the bottle rockets to become stable, and can also help affect “drag”.
2. What does Newton’s 2nd law have to do with rockets?
This means that for a bottle rocket, its acceleration depends (or is directly proportional) to its mass or amount of water that you use.
3. What does Newton’s 3rd law have to do with rockets?
To simplify Newton’s 3rd law, “What goes up, must come down”. Basically this relates to bottle rockets because once the bottle rockets are shot up, they must come down, showing that “for every action there is an equal and opposite reaction”.