Download Unit 4 - Youngstown City Schools

Youngstown City Schools
SCIENCE: PHYSICS
UNIT #4: NEWTON’S LAWS OF MOTION- - (4 WEEKS)
SYNOPSIS: This unit focuses on the concepts of Newton’s laws and the everyday effects of those laws on our daily lives.
Students will perform lab work to measure the effect of forces in several applications. Students will calculate the amount of
force used in several practical examples.
STANDARDS
VI.
NEWTON’S LAWS OF MOTION
A. The students will learn and demonstrate their knowledge of Newton’s laws of motion and how they are applied to
mathematically describe and predict the effects of forces on more complex systems of objects and to analyze objects
in free fall that experience significant air resistance.
B. The students will determine that an object will continue in its state of motion unless acted upon by a net outside force
(Newton’s First Law of Motion, the Law of Inertia).
C. The students will assess, measure, and calculate the conditions required to maintain a body in a state of static
equilibrium.
D. The students will assess, measure, and calculate the relationship among the force acting on a body, the mass of the
body, and the nature of the acceleration produced (Newton’s Second Law of Motion, F=ma).
E. The students will learn that forces from fluids will only be quantified using Newton’s Second Law and force diagrams.
F. The students will analyze and mathematically describe forces as interactions between bodies (Newton’s Third Law of
Motion).
G. The students will learn that when an object pushes on the particles in a fluid, the fluid particles can push back on the
object according to Newton’s Third Law and causes a change in motion of the object. This is how helicopters
experience lift.
H. The students will assess the independence of the vector components of forces.
I. The students will investigate, measure, and analyze the nature and magnitude of frictional forces.
J. The students will assess and calculate the nature and magnitude
K. The students will learn that gravitational interactions are very weak compared to other interactions and are difficult to
observe unless one of the objects is extremely massive.
L. The students will learn that the force law for gravitational interaction states that the strength of the gravitational force is
proportional to the product of the two masses and inversely proportional to the square of the distance between the
centers of the masses. Fg = (G·m1·m2)/r2). The proportionality constant, G, is called the universal gravitational
constant. Problem solving may involve calculating the net force for an object between two massive objects (e.g., Earthmoon system).
M. The students will demonstrate their knowledge that gravitational forces are universal phenomenon and gravitational
field strength is quantified.
LITERACY STANDARDS
RST.7 Integrate and evaluate multiple sources of information presented in diverse formats and media (e.g., quantitative data,
video, multimedia) in order to address a question to solve a problem.
RST.9 Synthesize information from a range of sources (e.g., texts, experiments, simulations) into a coherent understanding of a
process, phenomenon, or concept, resolving conflicting information when possible.
WHST.2 Write informative / explanatory texts, including the narration of historical events, scientific procedures/ experiments, or
technical processes.
a. Introduce a topic and organize complex ideas, concepts, and information so that each new element builds on that which
precedes it to create a unified whole; include formatting (e.g., headings), graphics (e.g., figures, tables), and multimedia
when useful to aiding comprehension.
b. Develop the topic thoroughly by selecting the most significant and relevant facts, extended definitions, concrete details,
quotations, or other information and examples appropriate to the audience’s knowledge of the topic.
c. Use varied transitions and sentence structures to link the major sections of the text, create cohesion, and clarify the
relationships among complex ideas and concepts.
d. Use precise language, domain-specific vocabulary and techniques such as metaphor, simile, and analogy to manage the
complexity of the topic; convey a knowledgeable stand in a style that responds to the discipline and context as well as to
the expertise of likely readers.
e. Provide a concluding statement or section that follows from and supports the information or explanation provided (e.g.,
articulating implication of the significance of the topic).
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TEACHER NOTES
MOTIVATION
1. Demonstrate each of the three laws: (students use previous experiences and knowledge)
a. An object in motion remains in motion until acted upon by an outside force: cup with
index card and penny; table cloth with dishes; egg with toilet paper roll over a
container of liquid - - where the objects are knocked so that it falls into the container
or the tablecloth is jerked out from under the dishes. Ask students what they believe
is happening? (e.g., gravity pulls the egg down) NOTE: do one of these here and
then use the other in the T-L section.
b. Force equals mass times acceleration (F=ma): roll a marble down a ramp; ask
questions as the marble rolls. Ask students to speculate what would happen if the
mass or size of the marble were changed, if the height of the track were changed, if
the force starting the marble would change, etc.
c. Every action has an opposite and equal reaction: put a tennis ball on top of the
basketball and drop them, the tennis ball goes to the ceiling; Newton’s Cradle. Ask
them what they think will happen before dropping and then why they think what
happened occurred.
Teachers: note that the
following website has lots
of great lessons for
different subjects in this as
well as other units.
http://phet.colorado.edu
2. Students set both personal and academic goals for this Unit.
3. Preview the authentic assessment
TEACHING-LEARNING
TEACHER NOTES
REFERENCE NOTES FOR TEACHERS ON NEWTON’S LAWS OF MOTION ARE
INCLUDED ON PAGES 4-17
NOTE: a Power Point
presentation of Newton’s
Laws is also part of this
unit.
1. Newton’s First Law: Teacher gives students real-world examples (e.g., driving and
running late, and slam on brakes and speed off from a red light) have students visualize
this and what do you experience. Tie their responses into Newton’s First Law. Do
demonstration on page 130 Demo #3 (VIB)
2. Students do No Net Force Lab (PASCO lab) TIM BAKOS (VIC)
3. Newton’s Second Law: Teacher gives students real-world examples (e.g., pushing a car - a 2 year old pushing or an 18 year old football player pushes the car). Have students do
The Skate Board Lab (Newton’s Skate Board Lab attached on pages 18-19); students
solve problems using F=ma; students will measure and calculate and diagram problems
using vectors of frictional forces. (VID; VIF; VIH; VI.I)
4. Newton’s Third Law: Have two sets of bathroom scales together (one on top of the other)
and have a student stand on the scale at the edge of the table. The student who reads
the weight on the bottom scale should see that the two scales show the same weight.
The force of the person pushing down on the table is equal to the force of the table
pushing up on the person. (NOTE: make sure scales are calibrated)(VIA;VIF)
5. Show video - - Quest Lab on Newton’s Laws of motion:
http://science.kqed.org/quest/video/quest-lab-newtons-laws-of-motion/ After students
look at this, teacher asks questions as to how each episode shows each law.
6. Teacher discusses and demonstrates factors that affect how fast an object will fall: refer
back to egg drop experiment and sky diver body position and discuss effect on free fall,
resistance, and acceleration. Answer questions from students.
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TEACHER NOTES
TEACHING-LEARNING
7. Forces and fluids: use Cartesian Diver as an example of forces in fluids; students can
experience this in small groups; they conclude that any time something moves, a force is
involved and they analyze how the movement occurs. Conservation of Matter is also
brought back into this discussion as nothing went into or out of the bottle. Students must
be able to diagram the forces inside the system with the diver and the water inside the
bottle. Relate to students the examples of change in pressure when going deeper under
water, ears “popping” on a roller coaster or on an airplane. Discuss scuba divers and
problem of “the bends.”
Calculate the pressure of water on a body using the equation P = mhg, where P =
pressure, m = mass, h = height, and g = gravitational acceleration. (VIE; VIF; VIG)
8. Gravitation: Teacher uses two different size balls and drops them; students see that
even though the balls are not the same size, they hit the ground at the same time (Free
Fall - - acceleration of a body due to gravity). Next show students that if you drop a piece
of flat paper vs a “wad” of paper, they do not fall at the same rate. Students conclude that
it is the surface area of a falling object that influences the rate at which it falls. Students
refer to results and discussion of the parachute egg drop lab from unit 2.
TRADITIONAL ASSESSMENT (20% of grade)
TEACHER NOTES
1. UNIT TEST
TEACHER NOTES
TEACHER ASSESSMENT (50% of grade)
1. 2- and 4-Point Questions
2. Lab Reports
TEACHER NOTES
AUTHENTIC ASSESSMENT(30% of grade)
1. Students evaluate their goals for the Unit.
2. Debate on the three laws of motion; see attachment at end of Unit - - (attached on pages
22-23). Research information on Newton’s laws and prepare an informative paper on one
of the three laws (RST.7, RST.9 and WHST.2 )
See the Folio for writing an
informational paper.
3. Competition Egg Drop with calculation sheets and rubric (attached on pages 24-26)
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Newton’s Laws of Motion
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Objectives

State Newton’s three laws of motion and display an understanding of their applications.

Demonstrate an understanding of the meaning of net force.

Distinguish between weight and mass and show how they are related.

Define inertia and its relationship to mass.

Demonstrate an understanding of the nature of frictional forces.

Understand the definition of free fall and the causes of air resistance and terminal velocity.

Describe the relationship between acceleration and force.

Describe the relationship between acceleration and mass.

Explain why the acceleration of objects in free fall do not depend upon the object’s mass.

Identify action-reaction forces when given an interaction.
Key Terms
kinematics
sliding (kinetic) friction
dynamics
air resistance
Newton’s First Law of Motion
terminal velocity
Newton’s Second Law of Motion
interaction
Newton’s Third Law of Motion
force
newton
net force
equilibrium
weight
mass
volume
normal force
inertia
friction
coefficient of friction
static friction
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Introduction to Newton’s Laws of Motion
Notes
So far we have studied linear motion, free fall, projectiles, vectors, and other ways to talk about things
that move. In a car you step on the gas; we can calculate the car’s acceleration, how long it takes to get
somewhere, or determine its direction. A projectile is fired; we can calculate its landing position, time of
flight, or velocity. So far we have only focused on how things move.
kinematics – the study of how objects move; Galileo’s focus of study.
There are other things to think about in terms of moving objects. In fact, it is the most asked question of
all two year olds: Why? The next several lessons answer the question: Why do things move the way
they do?
dynamics – the study of why objects move the way they do; Newton’s focus of study.
Newton’s Laws of Motion are all intertwined. To fully understand any one of them, you must know a
little bit about each one.
Newton’s First Law of Motion – an object at rest will stay at rest unless acted on by an outside force and
an object in constant motion will continue its motion unless acted on by an outside force; when no
forces act on an object, there is no acceleration; F = 0, a = 0.
Newton’s Second Law of Motion – acceleration is proportional to force, a  F ; acceleration is inversely
proportional to mass, a 
a
1
; therefore acceleration is proportional to the ratio of force to mass,
m
F 

; Fnet  ma .
m
Newton’s Third Law of Motion – for every action there is an equal and opposite reaction; the force in is
equal to the opposite of the force out; Fin = -Fout.
Forces
Demonstrations and Notes

Place a coin on the desk. Move the coin by pushing it sideways, observing the cause of the
motion. Stop pushing the coin, observing the motion of the coin. Determine what is required to
put the coin in motion. Place a ball on the desk. Gently push the ball sideways, observing the
motion of the ball. Determine what caused the ball to move. Determine what caused the ball to
continue to roll.
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force (F) – a push or a pull; vector; represented by vector arrows; all of the rules involving vectors apply
to force vectors.
newton (N) – units of force; 1
kg  m
.
s2
F = m a  kg

m kg  m
 2 =N
s2
s
Place a book on the table and push it to the right with a force of 10 newtons. Determine the force
being applied to the book due to pushing. Push the book with a force of 10 newtons to the right
and 10 newtons to the left. Determine the total force applied to the book due to pushing. Push
the book with a force of 8 newtons to the right and 10 newtons to the left. Determine the total
force applied to the book due to pushing.
net force (Fnet or F) – the combination or sum of all forces acting on an object; calculated using vector
addition.
Fnet  F  F1  F2    Fn
equilibrium – state of balance; occurs when F = 0 or net force acting on an object is zero.
Using Newton’s Second Law, Fnet = m a
If Fnet = 0, then either a = 0 or m = 0
Since mass never changes, m  0
Therefore when Fnet = 0 then a = 0
Another way to state Newton’s Second Law of Motion is when F = 0, a = 0; in other words, when no
forces act on an object, there is no acceleration.
Imagine a ball rolling across the table at a constant velocity. Since the ball is moving at a constant
velocity, there is no change in the velocity or no acceleration. Ignoring friction, there are no horizontal
forces acting on the ball. The obvious vertical force acting on the ball is gravity pulling it down. This is
the force due to its weight.
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weight (W) – the effect of gravity on an object, always acts down toward the Earth (negative).
mass (m) – the quantity of matter in an object.
volume (V) – the amount of space taken up by an object.
Using Newton’s Second Law, Fnet = m a. Since weight is a force, F = W.
Since the acceleration caused by the force is due to gravity, a = g
Since mass never changes, m = m
Therefore W = m g
Since the ball is traveling at a constant velocity, there is no acceleration; a = 0. According to Newton’s
Second Law of Motion, when there is no acceleration, the net force acting on the ball must also be zero,
Fnet = 0. If the weight of the ball is acting down, there must be another force acting on the ball in the up
direction to balance out the weight, producing a net force of zero. This force is known as the normal
force.
normal force (FN) –force perpendicular to the surface of contact.
When the surface of contact is horizontal, the normal force is equal and opposite to the weight of the
object on that surface, Fw = -FN,
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Summary Review – Introduction to Newton’s Laws of Motion and Forces








Newton’s First Law of Motion states that an object at rest will stay at rest unless acted on by an
outside force and an object in constant motion will continue its constant motion unless acted on
by an outside force.
Newton’s Second Law of Motion states that acceleration is proportional to the ratio of force to
mass, Fnet = m a.
Newton’s Third Law of Motion states that for every action there is an equal and opposite reaction.
A force is a push or a pull measured in newtons (N).
Net force is the combination or sum of all forces acting on an object.
When in a state of equilibrium, the net force acting on an object is zero.
Weight is the force of gravity acting down on all objects with mass.
The normal force is a perpendicular force that pushes surfaces together.
Inertia
Demonstrations and Notes

Cover the top of a glass with a note card. Place a coin on top of the note card. Flick the note card
sideways and observe what happens to the coin. Repeat with different objects of various mass.

Place a large hoop on a narrow flask. Balance a coin on top of the hoop. Hit the hoop sideways
very quickly and observe what happens to the coin.
Newton’s First Law of Motion – Law of Inertia; an object at rest will stay at rest unless acted on by an
outside force and an object in motion will stay in motion unless acted on by an outside force; when no
forces acts on an object, there is no acceleration; F = 0, a = 0.
inertia – the reluctance of any body to change its state of motion; measured by the mass of an object;
the larger an object’s mass, the more inertia it has.
The affects of inertia are easily seen when looking at a floater in a drink. When the glass is rotated, the
floater remains in the liquid at rest. To see the floater, the glass must be turned slowly so the inertia of
the glass and liquid move together.
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Things tend to keep doing what they are already doing. When outside forces (like friction, a push or pull,
and gravity) act on an object, the motion often changes. If friction is ignored, like in the vacuum of outer
space, an object at rest will never move and an object in motion will continue its motion at a constant
velocity forever!
Although a force is required to get an object moving, a force is not necessary to sustain the motion of the
object. However, frictional forces oppose motion causing objects in motion to eventually stop moving.

Place a tablecloth on the table and set up dishes on the tablecloth. Quickly remove the tablecloth
by pull it horizontally. Observe the dishes.

Hang a ball of large mass from a string. Connect another string to the bottom of the ball. Slowly
pull the string and observe the strings. Using the concept of inertia, determine which string will
break. Connect another string to hang the ball. Pull the lower string quickly. Using the concept
of inertia, determine which string will break.
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Summary Review – Inertia

Newtons First Law of Motion is often called the Law of Inertia.

Inertia is the reluctance of any body to change its state of motion and is determined by the mass
of an object.

Objects tend to keep doing what they are doing.

A force is required to get an object moving but a force is not necessary to sustain motion.
Friction
Demonstrations and Notes

Place a ball on the desk. Gently push the ball sideways, observing the motion of the ball.
Determine why the ball stopped rolling.
friction – force that acts between materials that touch; always opposes motion and shown parallel to
the surface of contact; caused by the irregularities in the surfaces of the objects touching.
The smoother the surface, the less friction that is present. Surfaces include the table, floor, air, or
anything composed of atoms. All objects interact differently with various materials. The way they
interact depends upon the composition of the material. The more rough a material, the more friction
that is present.
coefficient of friction () – constant that depends on the two surfaces in contact; no units; varies for
different materials; represents the percentage of force lost due to friction.


Ff
FN
 F f    FN
Place a book on the table and connect a spring scale to the book. Pull the book sideways and
observe the scale reading focusing on the reading when the motion begins. Observe the scale
reading after the motion has started.
static friction – the force that opposes the start of motion.
sliding friction – the opposing force between surfaces in motion; also called kinetic friction.
These types of friction are often experienced when moving large objects like a car. Initially, it is difficult
to get the car to move but once the motion starts, it is easier to maintain the motion.
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Air Resistance
Demonstration and Notes
There is another form of friction we have been ignoring up until now: air resistance.

Drop a ball and determine what forces act on the ball as it falls.
air resistance (Fdrag) – force of friction acting on an object moving through air; often called drag.
Since the ball is in free fall it is accelerating or increasing in velocity due to gravity. As the ball increases
speed the amount of air resistance also increases. This is observed when sticking your arm out the
window of a moving car. If the car is going slow (5 m/s) you can feel the air hitting your arm when you
stick it out the window. When the speed is increased (40 m/s) the air resistance is also increased as
noted by the way your hand jerks back when placed out the window. The same holds true for the ball in
free fall. As the velocity increase due to the acceleration due to gravity, the force due to air resistance
also increases, which decreases the acceleration of the ball.
Notice how the force of air resistance compares to the weight of the ball after a few seconds of free fall.
Eventually, the force of air resistance equals the weight of the ball. When this occurs, the net force
acting on the ball becomes zero. According to Newton’s First Law, when there is no force acting on an
object, there is no acceleration. This can only occur in two ways: no motion or constant velocity. Since
we know the ball is moving, the velocity must be constant.
terminal velocity – speed at which the acceleration of a falling object terminates because friction
balances the weight.
Fdrag = W
Fnet = 0, a = 0
The ball is now moving at a constant velocity
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Summary Review – Friction and Air Resistance

Friction is a force that acts between materials that touch.

Static friction opposes the start of motion.

Sliding or kinetic friction opposes the motion of an object.

Air resistance, or drag, is the force of friction acting on an object moving through air.

Terminal velocity occurs when the force due to air resistance of a falling object is equal to the
force of the object’s weight, creating a net force of zero to act on the object.
Free Fall Using Newton’s Second Law of Motion
Demonstration and Notes

Drop two balls of varying mass from the same height. Determine which ball will hit the ground
first.
Often it is said that gravity affects all objects the same. This is true, but to explain why gravity affects all
objects the same requires Newton’s Second Law of Motion.
Newton’s Second Law of Motion tells us that acceleration and force are proportional. If we only take
that into consideration, we are led to believe that the object that produces the larger force will
accelerate faster. The object with the larger weight will hit the ground first because it has a larger force
due to gravity and the larger the force, the greater the acceleration.
Newton’s Second Law of Motion also tells us that acceleration and mass are inversely proportional. If we
only take that into consideration, we are led to believe that the object with the smaller mass will
accelerate faster. Applying the concept of inertia, the less mass an object has, the easier it is to move. A
more massive object will resist motion and take longer to begin free fall. Therefore, since the smaller
object is easier to move due to its smaller mass, it will hit the ground first.
What we often fail to realize is that both force (weight) and mass affect an object in free fall. To
determine the acceleration of an object in free fall, use all of Newton’s Second Law of Motion.
F=ma a
F
m
Compare the ratios of force and mass for each falling object:
small ball 
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F
m
large ball
F

m
YCS Science: PHYSICS Unit 3 - - LINEAR MOTION 2012-13 13
The small ball has a small force of weight and a small mass. The large ball has a large force of weight
and a large mass. However, the ratios of force to mass for each object is equal! Since the ratios are
equal, each object has the same acceleration. This is also proven mathematically.
Small Ball: a 
F weight  9.8 N  9.8kg  m / s 2



 -9.8 m/s2 = g
m
mass
1kg
1kg
Large Ball: a 
F weight  98 N  98kg  m / s 2



 -9.8 m/s2 = g
m
mass
10kg
10kg
Summary Review – Freefall Using Newton’s Second Law of Motion


Both force and mass affect an object in free fall.
All objects fall at the same rate because the ratio of weight to mass is always constant.
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Action-Reaction
Demonstration and Notes

Push on a large object like the wall, a desk, or a closed door. Observe the forces acting on the
door and the person pushing.
Newton’s Third Law of Motion – for every action there is an equal and opposite reaction; the force in is
equal to the opposite of the force out; Fin = -Fout often called action-reaction.
When we think of a force, we usually speak of it as a push or a pull. Although that is true, a more precise
definition of a force would include the term interaction.
interaction – a mutual action between objects where each object exerts an equal and opposite force on
the other.
Interactions always happen in pairs. For example, you interact with the ground when you walk. You
push against the ground and the ground pushes against you. To determine the action and reaction
forces in an interaction, a simple formula is used.
Action: Object A exerts a force on object B.
Reaction: Object B exerts a force on object A.
To use the formula, simply determine what the object is acting on and reverse the roles. If you are
pushing on the wall, the wall is pushing on you, too!
Determine the action-reaction forces of the following interactions.
A car is cruising
down the street.
A rocket is lifting
off toward space.
A ball is dropped off
a very tall building.
The car’s tires push
down on the road.
The road is pushing up
on the car’s tires.
The rocket pushes down on
the gas (rocket fuel exhaust).
The gas pushes up
on the rocket.
The Earth is pulling
the ball down.
The ball is pulling
up the Earth!
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To understand how action-reaction forces work, look at the situation where a ball is falling toward the
Earth. If the action is the Earth pulls the ball down, then the reaction must be the ball pulls the Earth up.
It is true to say the ball falls down to the Earth. It is also true to say the Earth falls up to the ball! How
much the Earth moves is another story. In terms of force, the Earth and the ball apply an equal and
opposite force on one another. Comparing the mass of the ball and the Earth, it is obvious that the Earth
has a lot more mass. Using Newton’s Second Law of Motion, the acceleration of both the ball and the
Earth can be calculated.
The effects of Newton’s Third Law of Motion can be experienced and calculated using a less dramatic
example: firing a gun. The gun applies a force to the bullet and the bullet applies an equal and opposite
force to the gun. Since these forces are equal, they can be labeled as F. The mass of the bullet is small,
labeled small m, and the mass of the gun is large, labeled large m. To determine the acceleration of the
two objects, use Newton’s Second Law of Motion.
F=ma a
Bullet
F
m a
F
m
Gun
F
ma
The bullet has a much larger acceleration than the gun. In other words, the bullet is fired at a high
acceleration and the gun has a recoil of a small acceleration. The same thing applies to the falling ball
and the falling Earth. The difference is that the Earth has an enormous mass compared to the ball so the
acceleration of the Earth is so small we don’t even notice it!
Action-reaction forces are always equal in magnitude and opposite in direction. However, they do not
cancel one another out. This can be confusing, but by looking at the systems involved, the key to
Newton’s Third Law of Motion is revealed. (Even Newton admitted this concept was difficult to fully
understand!)
When looking at the systems of an interaction, the effect of the action-reaction forces in question are
dependent upon how the systems are defined. For example, when kicking a football, it is true to say that
your foot hits the ball and the ball hits your foot. The force you apply to the ball is equal and opposite to
the force the ball hits your foot. When viewing your foot and the ball as one system, it is true to say the
forces cancel out and produce no net force. However, when viewed independently, your foot hits the ball
with a force that will accelerate the ball. This holds true with Newton’s Second Law of Motion. The force
the ball applies to your foot is independent to the motion of the ball and does not cancel out.
Whenever action-reaction forces are internal to a system, they cancel each other out. They do not cancel
each other when either one is external to the system being considered.
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An excellent example of this concept is seen through the explanation of the horse-cart problem.
Summary Review – Action-Reaction


An interaction is a mutual action between objects where each object exerts an equal and opposite
force on the other.
Action-reaction forces do not always cancel each other out. They are dependent upon the
system.
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T-L
#3
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T-L #8
Physics Egg Drop
Situation:
Your mission is to design and construct a vehicle of restricted size that will protect its payload (a
large raw grade-A egg). The structure and packaging must protect the egg from breaking when
dropped from the second story of the high school building (approximately 20-30 ft.)
Problem:
Design a device with the lightest weight, the fewest number of parts, and the most accurate drop to
the Drop Zone Target (see equation on next page). The objective is to design the lightest possible
device that will prevent an egg from breaking or cracking when it is dropped from a height of at
least 25 feet. Your device must utilize a cushion design, not a parachute design.
Design Constraints:
 The device must be able to fit in a 12 in. cube and weigh less that 500g.
 The egg must be put into the device on the day of competition. The device must allow for easy
opening and inspection of the egg.
 Repairs requiring additional materials will not be allowed once the competition has begun.
 No propulsion or air drag devices (i.e., parachutes, helium, wings).
 The egg must be placed in a sealed plastic bag provided by the student before it is placed in
the container.
Suggested materials
Plastic straws
Cotton balls
Paper/cardboard box
Tissue paper
Cardboard rolls
toothpicks
rubber bands
string/twine
ladies stockings (nylons)
scotch/masking tape wood chips
pipe cleaners
plastic bottles
paper clips
paper/plastic cups
Illegal items: pre-constructed container, fruits or vegetables (popcorn is okay), powdered soap,
flammable substances of any kind, sponges, glass, duct tape, Styrofoam (or foam of any kind),
bubble wrap, items that will splatter (peanut butter, Jell-O, liquids, etc.), aerodynamic or restraining
devices, anything that may cause harm to a person or school property
Competition
1. Each vehicle will be inspected to determine compliance with the rules.
2. Each vehicle will be weighed at the competition. The weight will be measured in grams with no
egg inside.
3. The number of parts used for each device will be counted. Each individual piece will count as
one part. For example, if the egg is cradled in 100 cotton balls glued together, the device will
have 101 parts. 100 parts cotton balls and 1 part glue.
4. The Drop Zone will be comprised of three concentric rings: one, two, and three feet in
diameter. The Drop Zone Score will be determined by where the payload lands. Bull's eye – 1
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pt. Second ring – 2 pts Third Ring – 3 pts. Outside the rings – 4 pts. (numbers will be rounded
to nearest tenth of a point)
5. Each student will have two chances to qualify. The better score will be used.
6. Competition Scoring Formula
Score = [35(w/100) + 35(n/18) + 30 (DZ/2)] EIF
W = weight of the vehicle in grams
N = Number of parts
DZ = Drop Zone Score
EIF = Egg Integrity factor (1 if not cracked, .6 if cracked, .3 of broken)
Note: Formula is based on the ideal of a device that weighs less than 100 g, has less than 18
parts, and will drop in the first or second ring without breaking.
Bonus Criteria: create a vehicle that can safely carry the greatest number of eggs.
Documentation
 Submit a draft sketch of your egg vehicle with a list of supplies.
 Submit final documentation (to be provided) two days after the competition is completed.
Grading
Creativity – 25 pts. (A soda bottle filled with paper is not creative and will not protect the egg)
Meeting size and weight requirements – 15 pts
Egg survival Rate – 10 points
Competition placement – 75 pts
Documentation – 25 points
Bonus points: 5 points for each additional egg
Total value: - 150 pts.
Idea sketches and supply lists: __________________________________
Egg drop Date: _______________________________________________
All Documentation Due: ____________________________________
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AUTHENTIC ASSESSMENT: DEBATE ON NEWTON’S LAWS

Students will be paired off (or split into groups) and will randomly choose index card with
a law on it.

Students are to research three advantages and three disadvantages of each law.

Students must find two additional demonstrations of their law that were not covered /
discussed in lecture and perform these demonstrations the day of the debate.

Students will turn in their research notes prior to debating.

Students present their law to the class and perform two demonstrations.

Students debate the three laws, each taking turns presenting the advantages and
disadvantages.

Students write an argumentative summary from the debate about the three laws.
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AUTHENTIC ASSESSMENT: PARACHUTE EGG DROP
Name _____________________________
Objectives: Students will drop parachuted eggs to demonstrate the concepts of gravity, air
resistance, and terminal speed. Students will construct distance and velocity graphs to interpret
the acceleration of an object.
Pre-Lab Theory
Gravity is the force of attraction that causes objects to fall toward the center of the earth. Air
resistance, or air friction, can slow down the acceleration of a falling object.
The area “fronting the wind” affects the amount of air resistance a falling object encounters.
Terminal speed is the speed at which the downward pull of gravity is balanced by the equal and
upward opposing force of air resistance for a falling object.
Materials
 Lightweight plastic kitchen garbage-can liners; Scissors; Ruler; 20-inch lengths of light string; 3
plastic sandwich bags; 3 raw eggs
Procedures
1. From a lightweight plastic kitchen garbage-can liner, cut out three squares. Make one square
10” x 10”, a second square 20” x 20”, and a third square 30” x 30”.
2. Make a parachute out of each square by tying a piece of string to each corner of the square,
then attaching the other ends of the strings to a plastic sandwich bag.
3. Place a raw egg in each of the sandwich bags.
4. Predict which egg has the best chance of surviving a drop from about ten feet from the floor.
Explain the reasoning behind their predictions.
5. Drop each unfurled egg parachute from a height of ten feet, and then determine whether or not
your predictions were confirmed.
Discussion Questions
1. Describe the changing forces that acted on the parachutes as they fell and the resulting
changes in the parachutes’ motion. How did the falls of the larger parachutes differ from the
falls of the smaller ones?
2. Construct a distance vs. time graph for the following data: (D1 = 0 m, T1 = 0 sec), (D2 = 7 m,
T2 = 3 sec), (D3 = 14 m, T3 = 6 sec), (D4 = 21 m, T4 = 9 sec), and (D5 = 28 m, T5 = 12 sec).
Discuss how you would use this graph to determine the speed of the object being represented.
Is the object moving with constant speed or constant acceleration? Explain how you arrived at
your conclusion.
3. From the graph constructed in question 1, calculate the object’s speed at three-second
intervals, and then use this new information to construct a velocity vs. time graph for the object.
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Parachute Egg Drop Data Sheet
Distance
Time
Velocity
10” x 10”
20” x 20”
30” x 30”
10” x 10”
20” x 20”
30” x 30”
10” x 10”
20” x 20”
30” x 30”
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Acceleration
Physics Egg Drop RUBRIC
STUDENT NAME
Creativity
(25 pts.)
Size/Weight
(15 pts.)
Egg Survival
(10 pts.)
Competition
Placement
(75 pts.)
Score = [35(w/100) + 35(n/18) + 30 (DZ/2)] EIF
W = weight of the vehicle in grams
N = Number of parts
DZ = Drop Zone Score
EIF = Egg Integrity factor (1 if not cracked, .6 if cracked, .3 of broken)
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Documentation
(25 pts.)
Bonus For Addn.
Eggs
(5 pts.)
Drop Zone: Bull's eye – 1 pt. Second ring – 2 pts. Third Ring – 3 pts. Outside the rings – 4 pts.
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