Transcript Document

Straw Rocket
with Launcher
with a Nod to Newton
Newton notes based upon NASA STEM Liaison, Janet Raines,
Stomp Rocket presentation for the Oakley STEM Center.
What makes things move?
Who was the first scientist credited with exploring how
things move?
Galileo studied what makes things move,
exploring:
• falling objects
– gravity
– friction
– forces
Galileo Galilei
(1564-1642)
One scientist is known for the three physical
laws he discovered.
What is his name and what are his laws called?
Newton explained
Galileo’s discoveries
with his three “Laws
of Motion.”
Sir Isaac Newton (1642-1727)
Newton’s 1st Law
Law of Inertia
• An object at rest tends to stay at rest.
• An object in motion will stay in motion
at a constant speed in a straight line
unless acted on by a force.
*Inertia is the resistance to changes in motion.
Newton’s 2nd Law
Law of *Acceleration
F=ma
Force = (*mass) x (acceleration)
• The more force on an object, the more it
accelerates.
• The more massive an object is, the more it
resists acceleration.
Mass – the amount of matter in an object
Velocity – speed and direction of a moving object
Acceleration - change in velocity with respect to
time
Newton’s 2nd Law and Rockets
Law of Acceleration
• The more force (*thrust)
from the rocket engine,
the greater the acceleration.
• The lighter the rocket, the
greater its acceleration for a
given thrust.
Newton’s 3rd Law
Law of Action/Reaction
When one object exerts a force on a second
object, the second object exerts an equal but
opposite force on the first object.
What is a rocket?
• A rocket is a vehicle that is
self-contained and selfpropelled.
• It achieves motion from
Newton’s principle of a
reaction resulting from
every action.
Forces Acting on a Rocket
*Lift
*
*
*
*
Another View of Rocket Forces
How do Rockets demonstrate
Newton’s 3 Laws of Motion?
1st Law: The rocket stays at rest until
acted upon by a force.
Once in motion, the rocket tends to
stay in motion until acted upon by
a force.
2nd Law: The greater the force exerted on the
rocket, the greater its acceleration.
3rd Law: The thrust of the rocket fuel out of the
rocket pushes it away from the Earth.
Building a Straw Rocket
• We can explore how a rocket works with a
simple model built from a straw
• Instead of engines that fire to create the
thrust force…
• We will use a rubber band launcher to create
the thrust force
• Get ready!
Materials
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Scissors
Roll clear tape
Rubber band
Popsicle stick –
large
Straw – generic
(can be flexible)
Ball of modeling
clay 1 cm diameter
Plastic coated
paper clip
Set of 2 fin
templates
Fin Template
Cut the straw so that you remove the
flexible portion with the shorter end.
Fold paper clip into launch lug
Unfold paper clip into
“S” Shape.
Fold ½ of the
wide end of the
“S” to form a 90°
angle.
Do NOT create or attach
the launch lug if you are
using the Pitsco Straw
Rocket launcher.
Attach paper clip to straw ½ cm from end.
Wrap tape
around straw
and paper clip
at top and
bottom of
paper clip.
Do NOT create or attach
the launch lug if you are
using the Pitsco Straw
Rocket launcher.
Press clay onto straw at launch lug end
and form into a nose cone shape.
Be sure to press some of the
clay into the straw so that
you cannot shake it off easily.
Cut out and attach fins.
Cut out both fins –
they look like
arrow heads.
Wrap tape around straw at
tip and shaft. (Tape should
not intersect dotted lines.)
Attach second
fin in same way.
Fold arrows at
dotted lines to
make 4 fins!
Create launcher.
Stick a piece of tape parallel
to and on the end of the
popsicle stick.
Place a rubber band on the tape
at the tip of the popsicle stick.
Fold the tape over and onto the
popsicle stick. Place one more
piece of tape on in the same way.
Do NOT create this
launcher if you are
using the Pitsco Straw
Rocket launcher.
Wrap a piece of tape
perpendicular to and
around the popsicle
stick.
Launch the rocket!
Do NOT create this launcher
if you are using the Pitsco
Straw Rocket launcher.
Hold the rocket
parallel to the
launcher. Hook the
rocket to the rubber
band using the
launch lug.
Make sure you are not
aiming at anything alive
or breakable.
Pull the rocket back to
stretch the rubber band
tight. Let go of the rocket!
Discover the answers
• Does launch angle (the angle between horizontal
and line of popsicle stick launcher) affect the
distance your rocket flies?
• Does the amount of stretch you have in your
rubber band affect the distance your rocket flies?
• Does the mass of the nose cone affect the flight
distance?
• Can you predict how far the rocket will fly based
upon angle of launch and length of stretch in
rubber band?