After reading the background information please write a response that identifies 5 key factors in building a rocket.
This must be turned in your blue book journal at the end of class.
There are four basic forces operating on objects in flight such as a rocket.
They are gravity, thrust, drag and lift.
Gravity is the force that pulls all objects toward the center of the earth. The
amount of this force is proportional to the mass of the object.
Thrust is the force that propels the flying object.
Drag is the force acting on an object moving through a fluid. Since air and
water are fluids, drag is the resistance that the object encounters as it moves
through the fluid.
Lift is the force that is directed opposite to the force of gravity produced by
the shape and position of a body moving through a fluid. An object moving
in a vacuum produces no lift. Lift is generated by an object moving through
a fluid if the object’s shape causes appropriate reactions as the object moves
through a fluid.
Newton’s three Laws of Motion are concepts essential to understanding
rocket flight. The laws will be an integral part of the lessons in this unit.
The laws are as follows: 1. A body at rest will remain at rest, the body in
motion will continue in motion with a constant speed in a straight line as
long as no unbalanced force acts upon it. This law is often referred to as the
law of inertia.
2. If an unbalanced force acts on a body, the body will be accelerated; the
magnitude of the acceleration is proportional to the magnitude of the unbalanced
force, and the direction of the acceleration is in the direction of the
3. Whenever one body exerts a force on another body, the second body exerts
a force equal in magnitude and opposite in direction of the first body. This
law relates to the principle of action-reaction.
Lesson 1 (One Day)
Learning About Motion and Flight With a Model Rocket
Objective of the Lesson:
The student will be able to:
• Identify and trace the basic path of a rocket from launch to recovery.
• Describe how Newton’s Third Law of Motion relates to launching a
• Begin the construction of a rocket by assembling the engine mount.
• Recognize and define vocabulary.
Thrust is the upward force that makes the rocket accelerate upward. This is a
demonstration of Newton’s Third Law of Motion : “For every action there is
an equal and opposite reaction.” The action is the gas escaping through the
nozzle. The reaction is the rocket accelerating upward. The rocket will continue
to accelerate until all of the propellant in the rocket engine is used up.
The casing of a model rocket engine houses the propellant. At the base of the
engine is the nozzle, a heat-resistant, rigid material. The igniter in the rocket
engine nozzle is heated by an electric current supplied by a battery-powered
launch controller. The hot igniter ignites the solid rocket propellant inside
the engine which produces gas while it is being consumed. This gas causes
pressure inside the rocket engine, which must escape through the nozzle. The
gas escapes at a high speed. This produces thrust.
Above the propellant is the smoke-tracking and delay element. Once the propellant is
used up, the engine’s time delay is activated. The engine’s time delay produces a visible
smoke trail used in tracking, but no thrust. The fast moving rocket now begins to
decelerate (slow down) as it coasts upward toward apogee (peak altitude). The rocket
slows down due to the pull of gravity and drag. Drag is the force that resists the forward
motion of an object through the air.
When the rocket has slowed enough, it will stop going up and begin to arc over and
head downward. This high point is the apogee. At this point the engine’s time delay is
used up and the ejection charge is activated. The ejection charge is above the delay
element. It produces hot gases that expand and blow away the cap at the top of the
engine. The ejection charge generates a large volume of gas that expands forward and
pushes the parachute out of the top of the rocket. The parachute now opens and provides
a slow, gentle and safe landing. The rocket can now be prepared to launch again!
VOCABULARY Test Next Class
Accelerate: Speed up.
Gravity: The force that pulls all objects to the center of the Earth.
Apogee: The peak altitude a rocket reaches when it is farthest from the
surface of the earth.
Igniter: An electrical device that ignites the combustion of the propellant
in a model rocket engine.
Decelerate: Slow down.
Launch: The lift off of a model rocket following the ignition of the
Delay Element: Ignites after the propellant burns out and is an aid in
tracking the rocket and in providing a time delay during which the rocket
coasts to apogee.
Propellant: A mixture of fuel and an oxidizer which is the source of
motive energy in a rocket.
Drag: The force that resists the forward motion of an object as it moves
through the air.
Recovery System: The device in a model rocket whose purpose is to
return the rocket to the ground safely by creating excess drag or by
Ejection Charge: Ignited by the delay element and produces expanding
gases which activate or eject a recovery device.
Thrust: The force that makes the rocket accelerate upward as the propellant
After watching the video, students should identify 10-15 key points in the video.