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Day 3: Newton’s 2nd Law and Friction
Activity
Teacher
1. Review Newton’s
 Gives introduction for review
1st and 3rd Laws
o Draw or write a comic or story
demonstrating Newton’s 1st and 3rd Laws
o Brainstorm, plan, execute
 Circulates to help students
 Has students share with a partner and students fill
out rubric for how well story demonstrates laws
2. Mini-lesson on
 Leads discussion on acceleration and how it’s
acceleration
related to known vocabulary words (velocity,
force)
 Writes flow chart for determining acceleration on
board and goes through examples with students
 Introduces students to concept that acceleration
and force are related (don’t explain how, have
predict) Newtons’ 2nd Law
3. Newton’s 2nd Law
 Goes over instructions
Experiment
o Design an experiment to test Newton’s 2nd
Law (must change mass and force and
relate it to acceleration)
 Circulates to help groups



Student
Brainstorms ideas (5 min)
Plans and draws/writes (15
min)
Shares story with partner and
fills out rubric
Individual
 Participates in discussion
 Writes down definition of
acceleration
 Uses flow chart to determine
acceleration in examples
Whole class
 Designs an experiment to test
Newton’s 2nd Law
 Writes a generalization for 2nd
law based on experiment (40
min)
 Shares results with class (5
min)
Time
30 minutes
15 minutes
45 minutes
Group work
Break
4. Review of
Newton’s Laws


Makes a chart on board to review laws (3 rows)
o law in own words
o vocabulary associated
o how helps car challenge
Has students make class chart



Fills out chart on own paper
(10 min)
Shares answers for class chart
(10 min)
Fills out answers from class
chart into own chart
5 minutes
20 minutes
5. Mini-lesson on

simple force diagrams

6. Friction Activity





7. Finding Friction
All Write Round
Robin





Gives instruction on how to draw simple force
diagrams
o normal force, gravity, pushing, pulling,
friction, air resistance
o balanced forces, object does not move;
unbalanced forces, object does move
Goes over example situations after students do
group work
Emphasizes: forces determine acceleration
Leads discussion on friction (good and bad) and
elicits student experiences with friction
Gives instructions for activity
Circulates to help students
Has students share out findings
Reminds students of all write round robin
instructions
Has students look at cars and determine where
friction is
Has students brainstorm how to use friction in car
to their advantage
Circulates among groups
Has students turn in group list



Writes notes on simple force
diagrams (5 min)
Does examples in groups (5
min)
Shares out answers to
examples (5 min)
Whole class
Group work
 Gives examples of friction
and experiences with friction
 Students will test car speed on
different surfaces after
predicting how car will react
 Shares out observations
Group work
 Looks at cars and determines
where friction is (5 minutes)
 Brainstorms how to use
friction to make car faster
 Turns in group list
30 minutes
15 minutes
Group work
Clean-Up
MATERIALS
For each group:
car from Day 2
things to increase mass of car
masking tape
meter stick
stopwatch
ramp
15 minutes
5 minutes
WORKSHEETS
Newton’s Laws Review Rubric (ind)
Newton’s 2nd Law (group)
Friction Car Speed (group)
seran-wrap, sandpaper, aluminum foil to cover ramp
Race Car Design
Day 3
NAME:
MASTERY RUBRIC FOR NEWTON’S LAW REVIEW
4
The comic or story
shows Newton’s 1st law.
How?
3
The comic or story sort
of shows Newton’s 1st
law.
How?
2
The comic or story
doesn’t really show
Newton’s 1st law.
How?
1
No comic or story done
or the work is
incomplete.
Newton’s 3rd Law:
For every action there is
a reaction.
The comic or story
shows Newton’s 3rd law.
How?
The comic or story sort
of shows Newton’s 3rd
law.
How?
The comic or story
doesn’t really show
Newton’s 3rd law.
How?
No comic or story done
or the work is
incomplete.
Presentation
The comic looks good
and the storyline is
interesting
OR
The story is well written
and the plot is
interesting.
The comic looks okay
and the storyline is sort
of interesting
OR
The story is written
okay and the plot is sort
of interesting.
Not much effort was put
into the comic or story.
No comic or story done
or the work is
incomplete.
Newton’s 1 Law:
An object in motion
will stay in motion
and an object at rest
will stay at rest
unless acted upon by
an outside force.
st
NOTES:
TOTAL ___________
Race Car Design
Day 3
TEACHER NOTES
Acceleration Flow Chart
A bicycle messenger speeds up to make a green light and turn the corner.
Use the flow chart below to determine if the messenger is accelerating.
Is SPEED
changing?
YES
Is DIRECTION
changing?
YES
VELOCITY is
changing
NO
Is DIRECTION
changing?
NO
VELOCITY
is changing
ACCELERATION
YES
VELOCITY
is changing
NO
VELOCITY
is constant.
No Acceleration.
a=0
Race Car Design
Day 3
Acceleration Practice
1. John is riding his bicycle in a straight line at 6 m/s. He decides to go faster and
increases his speed to 8 m/s.
2. A merry-go-round is rotating at a constant speed.
3. Nancy is driving her car up 1st Avenue at 40 mph. As she turns on to 116th street,
she slows down her car.
4. Steve was rollerblading at a constant 5 m/s straight along the boardwalk at the
beach.
Simple FBD situations
1. Jane is rearranging the furniture in her room. She pushes her desk across the floor
to the opposite side of the room
2. Alex leaves a book at rest on his desk.
3. Two teams of students are playing tug of war. One team is stronger than the other
and pulls the rope with twice as much force as the other team.
4. A kid is in a swimming pool. He pushes on the side of the pool and accelerates
away from the side.
Race Car Design
Day 3
NEWTON’S 2ND LAW CAR SPEED TESTING
Names:
Group work, 45 minutes
Changing mass
Prediction: As the mass increases, the acceleration will be faster / slower (circle one) than normal.
How do you keep the force constant (so it doesn’t change)?
Procedure (what did you do?):
TRIAL DISPLACEMENT
Light
100 cm
Medium
100 cm
Heavy
100 cm
AVERAGE SPEED:
TIME
SPEED
VELOCITY
OBSERVATIONS
Race Car Design
Day 3
Changing force
Prediction: As the force increases, the acceleration will be faster / slower (circle one) than normal.
How do you keep the mass constant (so it doesn’t change)?
Procedure (what did you do?):
TRIAL DISPLACEMENT
Low
force
100 cm
Medium
force
100 cm
High
force
100 cm
AVERAGE SPEED:
Newton’s 2nd Law:
TIME
SPEED
VELOCITY
OBSERVATIONS
Race Car Design
Day 3
FRICTION CAR SPEED TESTING
Names:
Group work, 30 minutes
MATERIALS
How will you change the surface used for the test?
PREDICTIONS
Which material will slow down the car the most?
Which material will speed the car up?
MATERIAL DISPLACEMENT
100 cm
100 cm
100 cm
100 cm
TIME
SPEED
OBSERVATIONS
Race Car Design
Day 3