Physical Science CHS 2013-14
UNIT 2
Motion, Forces, Energy
• Entry Task
10/3/13
• If a car travelled 60 miles and it took the car 2 hours,
how many miles per hour was its average speed?
• Mathematically speaking, what does the “per” in the
above question mean?
• REMEMBER! All missing work for unit due tomorrow!
• HOMEWORK – start WHEN FINISHED WITH TEST:
Read pages 76-80. Answer all questions #1-10 on
page 80. Due Monday 10/7/13
Today’s Agenda
• Students needing more time on the test will
be finishing their tests.
• HOMEWORK – start WHEN FINISHED WITH
TEST: Read pages 76-80. Answer all questions
#1-10 on page 80. Due Monday 10/7/13
• PLEASE BE RESPECTFULLY SILENT AND SEATED
until all tests are turned in.
• EXTRA TIME? Complete the “Designing an
Investigation” Crossword for extra credit
10/3/13
• Exit Task
• What is your average speed if you walk 4
kilometers in 4 hours?
• Hint: speed
𝒅𝒊𝒔𝒕𝒂𝒏𝒄𝒆
=
𝒕𝒊𝒎𝒆
10/4/13
• Entry Task
• Say Something Nice
• For 2 free points!
• “What does the fox say?”
• Reminder HOMEWORK –: Read pages 76-80.
Answer all questions #1-10 on page 80. Due
Monday 10/7/13
Today’s Agenda – take notes with a partner
pages 76-85…complete as HOMEWORK!
Vocabulary – give meaning in
own words
•
•
•
•
•
•
•
Speed
Average Speed
Instantaneous Speed
Velocity
Distance
Constant speed
Slope
Key Ideas – take notes on these
ideas
What is the difference between
average speed and
instantaneous speed?
• How is velocity different than
speed?
• How do you show forwards and
backwards movement?
• What is the difference between
“distance” and “change in
position?
• What does a straight line mean
on a position vs time graph?
• How can you recognize a
relationship on a graph?
• How do you calculate slope?
What does slope also indicate?
• Sketch a position vs time graph.
• Sketch a speed vs time graph
10/4/13
• Exit Task
• Trade and Grade week of 9/30-10/4
• 2 more free points for your HIGH INTEGRITY grading
• Please be sure to only give points when it is earned!
• Reminder HOMEWORK –: Read pages 76-80. Answer
all questions #1-10 on page 80. Due Monday 10/7/13
• PLUS – C-notes vocab AND key ideas pages 76-85. Also
due Monday 10/7/13
10/7/13
Week of 10/7 to 10/11
• New Seating Chart
• Entry Task
• Dino can leap 400 meters in 30 minutes. This
includes brief sprints to catch butterflies.
What is his average speed in m/min?
• What is his average speed in m/hr?
• Can you tell his velocity? Why or why not?
Today’s Agenda
• Please get out p. 80 homework #1-10.
• Trade and Grade.
• Please also get out your C-notes vocab and
key ideas pages 76-85.
• Brief review with name cards….
• Turn in all homework!
• See next slide…planning an investigation.
Planning a Speed Investigation
• You will choose the independent variable.
• GOAL: find a way to increase the velocity of the car
once it crosses the photogate at bottom of ramp.
• Write down your independent variable choices:
–
–
–
–
–
–
–
–
Adding mass - mass balls – 1,2,3
Placement of mass balls – front, middle, rear hole
Rubber bands – distance stretched # of rubber bands – 1,2,3
Height of ramp
Placement of photogate – high, medium, low
Temperature of car – cold, warm, hot
Oil on axle – light, medium, heavy application
GREEN SHEET –
Designing an Investigation
• You will each complete all portions listed on green sheet in your
composition notebooks.
• TITLE
• Identify variables
• Question
• Hypothesis
• Materials and PROCEDURE
–
–
–
–
Be thorough and thoughtful with this section!
3 trials for each of 3 conditions
Experimental Control Condition
Extra Validity Measures
• DATA TABLE – I will post this…you add your groups labels and
measurements.
• Have design finished for tomorrow! Approval by start of class
tomorrow…
Condition
Experimental
Control
Condition
Condition 1
Condition 2
Condition 3
Trial 1
Time
Trial 2
Time
Trial 3
Time
Average
Time
Calculated
Speed =
𝟏𝒄𝒎
𝒕𝒊𝒎𝒆
10/7/13
• Exit Task
• What independent variable did your group
choose?
• What is your Hypothesis?
10/8/13
• Entry Task
• What is the “experimental control condition”?
• What are “extra validity measures”?
• For this lab, what will you do for both of the
above?
Today’s Agenda
• Get approval for your lab design before you
begin
• Be sure your data table is complete
• Be precise in your measurements.
• Complete data collection and calculating
averages and speed today.
• EXTRA TIME? Begin designing your graph.
10/8/13
• Exit Task
• What 3 controlled variables did you include in
your lab design?
10/9/13
• Entry Task
• We have calculated speed for our current lab:
𝒅𝒊𝒔𝒕𝒂𝒏𝒄𝒆
speed = 𝒕𝒊𝒎𝒆
• Why do you keep distance as 1 cm?
• Hint: how wide is the flag on the car?
• HOMEWORK: Speed Practice Sheet. Due Friday
10/11/13
Today’s Agenda
• EACH PERSON WILL:
• Collect and record data with their team.
Create a graph of your results – consult green
sheet.
• Draft and write conclusion – consult green
sheet.
• IN THEIR COMPOSITION NOTEBOOKS
10/9/13
• Exit Task
• Begin your conclusion from your data…
• Answer your investigative question, “How does (
your chosen independent variable)
• affect speed through the gate?”
• Was your hypothesis supported?
• HOMEWORK: Speed Practice Sheet. Due Friday
10/11/13
• Review Rubric
10/10/13
• Entry Task
• If I told you an object ACCELERATES 9.8 m/s each
second and I let it drop from a standstill…
• How fast would it be going after 1 second?
• Draw a picture to help you!
• REMINDER HOMEWORK: Speed Practice Sheet.
Due Friday 10/11/13
Today’s Agenda
•
•
•
•
•
•
•
Complete graphs.
Complete conclusions
Share good student examples.
See how many points you will get.
Partner Discuss
Fix yours where you need to.
Be ready to turn in tomorrow.
10/10/13
• Exit Task
• What does “acceleration” mean?
• How is this different than speed?
• REMINDER HOMEWORK: Speed Practice Sheet.
Due Friday 10/11/13
•
10/11/13
• Entry Task
• Say Something Nice
• For 2 free points!
• DUE DATES EXTENDED!!!
• HOMEWORK: Speed Practice Sheet. Due
Monday 10/14/13
• SPEED LAB: Due Monday 10/14/13
Today’s Agenda
• Pre-assessment of understanding of Motion,
Forces, Energy.
• Your score will NOT be your grade.
• You are graded on effort and completion.
• At the end of the unit, you’ll be given a similar
assessment and you can track your growth!
10/11/13
• Exit Task
• Trade and Grade
• For 2 free points…
10/14/13
Week of 10/14 to 10/18
• Entry Task
• Which unit would you use with acceleration?
• Why is the bottom letter “squared”?
Please take out your homework…
•
•
•
•
•
Trade and Grade math problems. Grader sign at top.
DO NOT COPY ANSWERS FROM BOARD = cheating.
Self-assessment of lab investigation.
See Ms. Maring’s example.
Grade your own by carefully writing the points
earned in the margin.
• ALSO, circle on your rubric what you did not
include.
• PLACE YOUR RUBRIC in your comp book by the lab.
Turn in to comp book shelves. I will lock them.
Today’s Agenda
• Hand back papers and organize into binders.
• If you are on the PASSING list for the Unit 1
test, you may design a lab based on one of the
other independent variables. See sheet.
• Form a team of 3-4 and collect data for that
independent variable on the provided data
table.
• If you are in the REQUIRED REFLECTION group,
you will join me for a discussion of the test
Condition
Experimental
Control
Condition
Condition 1
Condition 2
Condition 3
Trial 1
Time
Trial 2
Time
Trial 3
Time
Average
Time
Calculated
Speed =
𝟏𝒄𝒎
𝒕𝒊𝒎𝒆
Passed Unit 1 test – “on your own”
further investigative question lab
• You will choose a different independent variable
from this list…
–
–
–
–
–
–
Adding mass - mass balls – 1,2,3
Placement of mass balls – front, middle, rear hole
Rubber bands – distance stretched # of rubber bands – 1,2,3
Height of ramp
Placement of photogate – high, medium, low
• Form a team of 3-4 with the same choice, write a
brief lab design and collect data.
• Please clean up and return materials when
finished.
REQUIRED REFLECTION – Unit 1 test
• If you had a score of 60% or below, you are required to
reflect.
• Please get out a piece of notebook paper.
• Review reflection instructions.
• You will be given the test back for this class period only. If
you need more time, please schedule with me before/after
school to use the test.
• For each question you are seeking points back,
• Write down the PROBLEM NUMBER and answer a, b, c, d.
• The correct answer is shown in RED on your scan-tron paper.
You may write down the answers on your written sheet.
• You will staple your scan-tron and written section to your
reflection.
10/14/13
• Exit Task
• How could you show a change in velocity
WITHOUT a change in speed?
• What is another name for “change in
velocity”?
10/15/13
• Entry Task
• Please sketch a graph of the following (x axis time; y axis
velocity)
• From the river to the woods, Little Long-legs Red Riding hood
accelerated from a starting velocity of 0.5 m/s to 1 m/s after
60 seconds. At the woods, she got scared and began running
to grandmother’s house, accelerating from 1 m/s to 10 m/s in
30 seconds and then continued at that constant speed for the
next 2 ½ minutes.
• HOMEWORK DUE THURSDAY 10/17/13: Read pages 86-93.
Answer questions #1-11 on page 93.
• REMINDER – you will need to bring your calculator EACH day
for the rest of this unit!!!
Acceleration
STANDARDS – performance
expectations
• I can calculate the average acceleration of an
object, given the object’s change in velocity
𝑣2−𝑣1
with respect to time. (a =
)
𝑡2−𝑡1
• I can explain how an object moving at
constant speed can be accelerating.
Acceleration
• a change in velocity (speed or direction or
both) over time
– speeding up or slowing down
– changing direction
• moving in a circle is always changing
direction
Changing direction
http://phet.colorado.edu/en/simulation/moving-man
Negative acceleration
• if acceleration is a negative number it is
referred to as negative acceleration or
deceleration
Think “braking!”
The steeper the hill, the greater the
acceleration…
Not very steep. Adding
1 m/s to the speed each
second.
Very steep. Adding
2 m/s to the speed each
second.
Greater acceleration will be a steeper
slope on a speed vs time graph
Zero Acceleration
• there is zero acceleration at constant speed
because the speed does not change.
Think “cruise control”!
(As long as direction stays
the same…)
Math for Acceleration
a
𝑣2−𝑣1
=
𝑡2−𝑡1
a = acceleration
𝑣2 = speed at finish
𝑣1 = speed at start
t = time
𝑡2 = time at finish
𝑡1 = time at start
Sometimes 𝑡2 − 𝑡1
may simply be
“t”
Same math as in your book…p 87
• Don’t write this down…
Example problem
• A car is traveling at 3.4 m/s. After 3
seconds, it is now traveling 8.2 m/s.
Calculate its acceleration.
Looking for:
Solution:
acceleration
Given:
V1 = 3.4 m/s
V2 = 8.2 m/s
T = 3 seconds
Formula:
a
𝑣2−𝑣1
=
𝑡2−𝑡1
a=
8.2𝑚 3.4𝑚
−
𝑠
𝑠
3 𝑠𝑒𝑐𝑜𝑛𝑑𝑠
a=
4.8 𝑚
𝑠
3𝑠
= 1.6
𝑚
𝑠2
10/15/13
• Exit task
• A bike is traveling at 2.0 m/s. After 3
seconds, it is now traveling 5.0 m/s.
Calculate its acceleration.
Looking for:
Solution:
Given:
Formula:
HOMEWORK DUE THURSDAY 10/17/13: Read pages 86-93. Answer
questions #1-11 on page 93.
REMINDER – you will need to bring your calculator EACH day for the rest of
this unit!!!
10/16/13
• Entry task
• A bird is flying at 6.0 m/s. After 2 seconds,
it is now flying 2.0 m/s. Calculate its
acceleration.
Looking for:
acceleration
Given:
Formula:
V1 =
V2 =
T=
a
𝑣2−𝑣1
=
𝑡2−𝑡1
Solution:
Designing the Investigation
• Question: How does placement of photogates
affect acceleration of the car?
• Make a prediction:
• If the photogates are further apart
• Then ________________________
• Because______________________
• Controlled variables:
Acceleration Lab
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•
•
•
•
•
•
•
•
•
•
•
•
C-clamps at far top and far bottom of ramp. Ramp in 5th hole from bottom.
Photogate 1 will be at top black square mark.
Photogate 2 will be 10 cm below that.
Photogate 3 will be at first black mark below middle of ramp
Photogate 4 will be 20 cm below that.
Run car from top of ramp. Record time at each photogate. And Record time
between photogates. Repeat for 3 trials.
Sit down to calculate averages, velocity and acceleration.
We will calculate velocity at photogate 1 as v1.
We will calculate velocity at photogate 2 as v2.
Then we can calculate acceleration as change in velocity with respect to time
between photogate 1 and 2.
We will calculate velocity at photogate 3 as v1.
We will calculate velocity at photogate 4 as v2.
Then we can calculate acceleration as change in velocity with respect to time
between photogate 3 and 4.
Condition Trial 1
Time
Trial 2
Time
Trial 3
Time
Average Calculated
Time
Speed =
𝟏𝒄𝒎
V=
𝒕𝒊𝒎𝒆
Photogate tA =
1
tA =
tA =
𝑣1 =
Photogate tB =
2
tB =
tB =
𝑣2 =
tAB =
tAB =
tAB =
Photogate
3
Photogate tB =
4
𝑣1 =
tB =
tB =
𝑣2 =
AvgTime
from
A to B
(𝑡𝑨𝑩)
Calculated
Acceleration
a
𝑣2−𝑣1
=
𝑡𝑨𝑩
10/16/13
• Exit Task
• Did the car accelerate as it rolled down the ramp?
In other words, were there changes in the car’s
velocity over time (or between photogates)?
• Use data from your data table to back up your
answer!
• REMINDER HOMEWORK DUE TOMORROW
10/17/13: Read pages 86-93. Answer questions
#1-11 on page 93.
10/17/13
• Entry Task
• Imagine yourself on a bicycle or skateboard what
outside influence would cause you to accelerate
or decelerate?
• Per 1 – Earthquake drill prep
• Please take out your homework - pages 86-93.
Answer questions #1-11 on page 93.
• Trade and Grade – turn in.
Today’s Agenda
• You will be doing 1 of the following:
• REFLECTION on Unit 1 Test – required if you
failed…optional if you want to improve your
grade. TESTS ONLY AVAILABLE IN
CLASSROOM.
• EXTENSION LAB for extra credit.
• Acceleration Lab Analysis
Questions….otherwise this will be
homework…
10/17/13
• Exit Task
• Trade and Grade week of 10/14 to 10/17.
• HOMEWORK – please complete Acceleration
Lab Analysis Questions for Monday.
10/18/13 NO SCHOOL
• Teacher Inservice
10/21/13
Week of 10/21 to 10/25
• Entry Task
• Explain all parts of a good conclusion.
(Consult the green sheet.)
• What does “gives the data….” mean? How
would a good conclusion include data? What
kind of data?
• Please get out your acceleration lab and lab
analysis questions (That was your homework!)
Today’s Agenda
• Hand back papers and organize into binders.
• Final day for Unit 1 reflections.
• Play Jeopardy to study for Quiz tomorrow.
– RULES:
– There will be two teams.
– Each row on a team will have a whiteboard to
write answers. Nominate a recorder.
– When the question is displayed, all rows will
huddle to discuss and record correct answer.
– Each row to get the answer correct receives the
points at stake.
– The team with the most points at the end WINS!
10/21/13
• Exit Task
• What do you need to study tonight?
• Which resources will you use?
• Entry Task
10/22/13
• Prepare for the quiz.
• Please turn in your homework – acceleration
lab and analysis questions plus graphs.
• You may have a pencil or pen,
calculator, and your acceleration
notes ONLY on your desk for the
quiz.
• Everything else under desks.
QUIZ
• Talking or looking at another student’s paper will
be considered cheating = zero on quiz and
reported.
• When completed, please check your work.
• Raise your hand for an adult to pick up your quiz.
• Finished early? Start on HOMEWORK.
• Two parts Due Friday 10/25/13 :
– Read pages 97-104. Answer questions 1,2,4,6,7,8 on
page 104.
– Read pages 107, 109, and 112 and 114-119. Answer
questions 1,2,3,4,5,8 on page 119
10/22/13
• Exit Task
• None – testing
• HOMEWORK.
• Two parts Due Friday 10/25/13 :
– Read pages 97-104. Answer questions 1,2,4,6,7,8 on
page 104.
– Read pages 107, 109, and 112 and 114-119. Answer
questions 1,2,3,4,5,8 on page 119
10/23/13
• Entry Task
• What would you call a “push or pull” on an object?
• If this “push or pull” occurred on an object, what do
you think the results would be for the object? Describe
in terms of speed, direction, or acceleration.
• HOMEWORK - Two parts Due Friday 10/25/13 :
– Read pages 97-104. Answer questions 1,2,4,6,7,8 on page
106.
– Read pages 107, 109, and 112 and 114-119. Answer
questions 1,2,3,4,5,8 on page 119
Forces
Newtons, Friction, Gravity, Weight
and Free Body Diagrams
STANDARDS
• When given specific scenarios, I can compare the motion of an object acted
on by balanced forces with the motion of an object acted on by unbalanced
forces.
• I can predict how objects of different masses will accelerate when subjected
to the same force.
• I can calculate the acceleration of an object, given the object’s mass and the
net force on the object, using Newton’s Second Law of Motion (F=ma).
• Using everyday examples, I can illustrate that for every action there is an
equal and opposite reaction (e.g., a person exerts the same force on the
Earth as the Earth exerts on the person).
• I can predict how the gravitational force between two bodies would differ for
bodies of different masses or different distances apart.
• I can explain how the weight of an object can change while its mass remains
constant.
5.1 The cause of forces
• A force is a push or pull, or an action that has
the ability to change motion.
• Forces can increase or decrease the speed of a moving
object.
• Forces can also change the direction in which an object
is moving.
5.1 Newtons
• Although we use pounds all the time in our
everyday life, scientists prefer to measure forces
in newtons.
• The newton (N) is a metric unit of force.
Forces act during Direct Contact
• A contact force is transmitted
by matter directly touching
other matter such as wind
acting to slow a parachute.
Forces act over a distance
• The force of gravity between
Earth and Moon appears to be
what people once called
“action at-a-distance”.
• Today we know that the
gravitational force is carried
from the Earth to the Moon by
a force field.
Force of Gravity = weight
• The force of gravity on an object is called
weight.
• At Earth’s surface, gravity exerts a force of
9.8 N on every kilogram of mass.
Weight depends on mass and gravity
A 10-kilogram rock has the same mass no matter where
it is in the universe. On Earth, the10 kg. rock weighs 98
N.. On the moon, the same rock only weighs 16 N.
5.2 Friction
•
•
Friction is a force that
resists the motion of
objects or surfaces.
Many kinds of friction
exist.
5.3 Adding forces
•
•
To figure out if or how an object will move,
we look at ALL of the forces acting on it.
For example - Four forces act on a plane:
1.
2.
3.
4.
weight
drag (air friction)
the thrust of the engines, and
the lift force caused by the flow of air over the
wings.
5.3 Normal forces
•
•
When the forces are
balanced, the net force
is zero.
When the net force on
an object is zero, we
say the object is in
equilibrium.
5.3 The free body diagram
•
•
How do you keep track
of many forces with
different directions?
Draw a free-body
diagram that contains
the objects, like a book
on a table.
= direction of motion
gravity
me pushing
sliding friction
normal force or the table
10/23/13
• Exit Task – based on the following forces,
which way will the plane move?
10/24/13
• Entry Task
• Recall the cars on the ramps. At the moment you
release the car, draw a free-body diagram
showing all the forces.
• HOMEWORK - Two parts Due Friday 10/25/13 :
– Read pages 97-104. Answer questions 1,2,4,6,7,8 on
page 106.
– Read pages 107, 109, and 112 and 114-119. Answer
questions 1,2,3,4,5,8 on page 119
Name_____ Partners _______ ________
Observing Forces at Work
• Purpose
– Observe various forces and their direction at 1-8 lab
stations.
• Procedure
– Draw a free-body diagram of the forces involved at
each station.
– vectors should show the DIRECTION and RELATIVE
STRENGTH of forces
– try to label the vectors with the TYPE OF FORCE
» contact: sliding, rolling, static, fluid friction, or normal force…
» non-contact: magnetism, electrical, gravity…
– if necessary, an explanation can accompany your freebody diagram or use different arrows to show movement
Today’s Agenda
• Finish notes.
• Complete all the lab stations in any order in
your composition notebook.
• When finished, sit down and work on the
worksheet of Free Body Diagrams.
• Complete diagrams on the back or on your
own paper.
• Finished early? Work on your homework for
tomorrow!
10/24/13
• Exit Task
• Draw the forces on the Newton’s Cradle at the
moment of impact.
• Extra Time? Draw another when the ball is at
the peak of its swing.
10/25/13
• Entry Task
• Say Something Nice
• Please take out your homework. What
percentage did your class achieve?
• Make sure your name is at the top.
• Trade and Grade.
Today’s Agenda
• Complete Lab Activity from Yesterday.
• Work on and turn in Free Body Diagram
Practice Sheet. Due Monday.
• Extra time? Next force lab – complete
activities at each station in composition
notebook.
10/25/13
• Exit Task
• Trade and Grade
10/28/13
Week of 10/28 to 11/1
• Entry Task
• Using the textbook or your own knowledge,
explain Newton’s First Law of Motion.
• Review and Turn in Free Body Diagram
Practice.
Today’s Agenda
• Watch Newton’s Laws of Motion video and
take notes – 15 min
• Summarize the 3 Laws in your own words. - 5
min
• Watch Road Runner – 10 min
– Raise hand to pause and discuss when you notice
a law in action
– OR objects “ignoring” Newton’s Laws
• Review Project Details/Student work and
Begin Brainstorm – continue tomorrow…
10/28/13
• Exit Task
• From your notes, explain Newton’s Second
Law of Motion.
10/29/13
• Entry Task
• Watch Ms. Maring’s demonstration. {I will place
a paperclip on a notecard on a beaker. I will flick
the notecard strongly and the paperclip will fall
into the beaker when the notecard moves out
from under it.}
• Explain the motion of the objects in terms of
Newton’s Laws.
• TURN IN YOUR HOMEWORK! The free body
diagram practice!
Today’s Agenda
• GOAL – by end of class have storyboard draft
complete.
• Who will your characters be? What will they
do to show Newton’s 3 Laws?
• Whatever you do not finish is homework.
• You will get peer feedback tomorrow in order
to revise and finalize your cartoon.
10/29/13
• Exit Task
• Briefly explain how the actions of your
characters show Newton’s Laws:
• 1. Inertia – staying at rest or in motion
• 2. F = ma (greater mass requires greater force
for equal acceleration)
• 3. Equal and Opposite action/reaction forces.
10/30/13
• Entry Task
• If you triple the mass but keep the same force,
what happens to the acceleration?
• NOTE: you can rewrite F = ma as
• a=
𝐹
𝑚
• REMINDER – you should have a complete
storyboard draft to share after entry task!
Today’s Agenda
• In your small groups, you will each share your
cartoon – read it, point out how you showed
the laws. Please take turns and don’t
dominate the time.
• On Say Something Nice slips, each person will
give feedback – one great thing and one area
of concern.
• Following feedback, you can begin on final
draft. Please consider suggested revisions.
Cartoon Peer Workshop
•Groups of 3 or 4
•Each person present draft storyboard–
explaining motion and ideas, and what you plan to add
•Suggest what feedback you are looking for –
For example, help representing the laws, or help with your storyline, or help
with the artwork itself, or help with the dialog, etc
•Each listener will jot down some notes or comments for constructive
feedback on the pieces of scrap paper.
•Do be respectful and follow workshop guidelines!
Peer Workshop Etiquette
• All comments have to be constructive. No trash
talking allowed.
• You have to comment on the work in front of you,
not what you would have written if it had been
your idea. Even if you think your idea is better.
• Don't try to rewrite for the author. The author
can do that him/herself. Just point out the areas
of concern.
• (borrowed from Meir Ribalow of a NYC playwright’s group)
10/30/13
• Exit Task
• Look at the picture on page 136 in your
textbook. Why, if the reaction/action forces
are equal, does the elephant have less
acceleration?
10/31/13
• Entry Task
• Calculate the acceleration if a car’s mass is
1000 kg and a net force of 2000 N is exerted
on the car. Show your work!
Today’s Agenda
• Complete Final Drafts of cartoons.
–
–
–
–
–
–
Your packet should be paperclipped and include:
Rubric on top with name
Summary of laws on notes
Rough Draft Story Board
Final Draft Cartoon
Written Summary of how you showed the laws
• NEWTON CARTOONS DUE FRIDAY START OF CLASS…but
you can turn them in today…
• HOMEWORK – read pages 125-138.
• On page 135, answer # 3,4,6,7
• On page 143, answer # 6a, c
• DUE MONDAY November 4
10/31/13
• Exit Task
• How much force would you need to accelerate
a 20 kg object to 20 m/s2?
HOMEWORK – read pages 125-138.
On page 135, answer # 3,4,6,7
On page 143, answer # 6a, c
DUE MONDAY November 4
11/1/13
• Entry Task
• Say Something Nice
•
•
•
•
HOMEWORK – read pages 125-138.
On page 135, answer # 3,4,6,7
On page 143, answer # 6a, c
DUE MONDAY November 4
Today’s Agenda
• Introduce Egg Drop – designing your project is
additional homework for the weekend.
• Complete self assessment regarding
standards.
• Return and graph pre-assessment.
• Set Goals.
Egg Drop – write in your
composition notebook!
• Problem: Design a container that will keep an egg
from breaking when dropped from the school roof.
• Constraints: When dropped from the roof, the egg
can’t break.
• Criteria:
– The vessel must be as low in mass and
– As small in size as possible to keep the egg safe.
Background Information
•Egg will be provided day of the drop
– Tuesday, Nov. 5th
•No parachutes, propellers, gliders, or
Helium balloons…
•No glass or anything dangerous
•No motors or engines of any kind
•The egg must be returned in original
condition for points
Point Values for Container
• Size:
– 10 cm X 10 cm = 4 points
– 20 cm X 20 cm = 3 points
– 30 cm X 30 cm = 2 points
– Larger = 1 points
• Mass
– Egg mass = 60 g.
– Less than 50 g container = 4 points
– 50 - 100 g container = 3 points
– 100 - 150 g container = 2 points
– 150 -200 or larger = 1 points
Due Monday:
Labeled sketch with written description (4 pts.)
Due Tuesday:
YOUR CONTAINER!!! You can bring it Monday
(8 pts possible if both light and small)
Wednesday: Analysis (8 pts.)
If your egg survived:
1. Write an explanation of how your design protected the egg
(include a discussion of forces).
2. If you could redesign your container, how could you make it
smaller and lighter, while maintaining its ability to protect the
egg?
If your egg did not survive:
1. Write an explanation of why your design did not protect the
egg (include a discussion of forces).
2. If you could redesign your container, how could you make it
work to protect the egg, while still trying to keep it as small
and light as possible?
11/1/13
• Exit Task
• Trade and Grade
11/4/13
Week of 11/4 to 11/8
• Entry Task
• Find a definition for Law of Universal
Gravitation in textbook.
• Please turn in your homework from pages 135
and 143.
Today’s Agenda
• Listen and take notes about the law of universal
gravitation.
• Use the basic formula to solve problems.
•
•
•
•
•
•
𝑚1∙𝑚2
𝑟2
F=G
G won’t change.
F is force
m1 and m2 are the masses of the objects
r is the distance between them.
Work through #1 together.
11/4/13
• Exit Task
• Explain how your egg drop container will
protect the egg?
• Reminders: Tomorrow Ms. Maring will check
your designs and explanations. AND you need
to bring the actual container for the Egg Drop!
11/5/13
• Entry Task
• Please put your name on project…turn in to shelf.
• If you increase the distance between objects,
what happens to the force of gravity between
them?
• Explain using F = G
𝑚1∙𝑚2
𝑟2
• Please get out your law of universal gravitation
worksheets from yesterday.
Today’s Agenda
• Watch Phet Simulation
• Review law of gravitation sheet – turn in.
• Egg drop TOMORROW because I need to buy
more eggs!
• Find mass and size of egg drop container.
11/5/13
• Exit Task
• The moon has much less mass than the sun.
Why would it have a greater affect on the
tides?
• Explain using F = G
𝑚1∙𝑚2
𝑟2
11/6/13
• Entry Task
• 2 objects are originally attracted to each other
with 16 units of force. What will the new force
be if the distance quadruples?
• EGG DROP CONTAINERS IN CUPBOARD….drop has
to be tomorrow due to short classes today.
• Please turn in your Universal Gravitation HW.
Today’s Agenda
• Complete red sheets with pre-test graph and
goals.
• Hand back papers.
• Review quiz answers
• 12 or less = REFLECTION required. Anyone can do
a reflection to get points back.
• Extra Time - NOTES:
• A little more about gravity and how to calculate
weight.
11/6/13
• Exit Task
CANCELLED due to
short classes.
• We have learned a number of formulas in this
unit. Write down TWO and explain each of
the parts.
• Choices: speed or velocity, acceleration,
Newton’s 2nd Law, universal gravitation.
11/7/13
• Entry Task
• Seating chart
• Explain how your egg drop materials meet the
criteria for least size and mass.
Today’s Agenda
• 10 minutes - Insert eggs into containers to
prepare for drop.
• 10 minutes - Place your project on your comp
book opened to your design.
• I will record mass and size.
• 15-20 minutes - You will exit out the door by
horticulture and stand near cafeteria.
• Let me know if there is a particular way to drop
your egg container.
• Collect containers into bag
• 10 minutes - Return to classroom to assess
casualties and write analysis.
11/7/13
• Exit Task
• Summarize how you would improve your
design in terms of mass, size or better
protection.
• For 8 points – your written analysis is due on
Tuesday – you will turn in your comp book.
11/8/13
• Entry Task
• Say Something Nice
• For 8 points – your written analysis is due on
Tuesday – you will turn in your comp book.
Today’s Agenda
• Watch the video • Answer the reflection questions on your own
paper.
• These answers will be due Tuesday with your
Egg Drop Analysis.
11/8/13
• Exit Task
• Describe 2 aspects of Newton’s life which were
different than you might have expected of a great
scientist.
• PLEASE TURN IN YOUR ENTRY/EXIT TASK SHEETS!!
• For 8 points – your written analysis is due on
Tuesday – you will turn in your comp book.
11/12/13
• Entry Task
• Compare mass and weight – how are they the
same and different?
Today’s Agenda
• Discuss Questions about Sir Isaac Newton
• Turn in Composition Books with Egg Drop
Analysis Questions
• Hand Back Papers – binder organizing session
• 20 minutes – notes on Weight and Gravity
• Practice Problems: Mass, Weight, Gravity due
Friday
11/12/13
• Exit Task
• Compare Newton’s Second Law formula F=ma
to the formula for weight W = mg
• Remember, here “g” is acceleration due to
gravity.
11/13/13
• Entry Task
• Find a definition of WORK in your physical
science textbook.
• Explain how this is different than our everyday
understanding of the word “work.”
Today’s Agenda
• Notes on Weight and Gravity
• Practice Problems: Mass, Weight, Gravity
Worksheet due Friday November 15 2013.
Gravity and Weight
• Zeus has the following:
1. golf ball (70 grams)
2. foam ball (30 grams)
3. plastic ball (15 grams).
• He holds them all exactly ten inches off the ground
and drops them at the exactly the same time.
• In what order will they hit the ground?
– I. 1,2,3
– II. 3,2,1
– III. all at the same time
• It is “said” that Galileo first dropped two
cannonballs off the Leaning Tower of Pisa in Italy
– one was 10x heavier than the other
– they both hit the ground at the same time
Without air resistance, all objects fall
at 9.8 m/s2 (on earth)
• http://www.youtu
be.com/watch?v=
_XJcZKoL9o&feature=rel
ated
• http://www.physic
sclassroom.com/cl
ass/1dkin/u1l5e.cf
m
• Newton used Galileo’s research to conclude
that objects accelerate downwards because
of the force of gravity between the object
and the earth
• this acceleration is 9.8 m/s/s (or 9.8 m/s2) in
a vacuum (no air)
• however realistically, air resistance (fluid
friction) often prevents many objects from
accelerating this fast
Weight
• a measure of gravity’s force on an object that is
directly proportional to its mass
– this means gravity pulls more on objects that
are bigger
– it does NOT mean it will fall faster
• weight can change depending on the force of
gravity
– you weigh less on the moon than on the Earth
because the moon has less gravity
• http://csep10.phys.utk.edu/astr161/lect/histo
ry/newtongrav.html
Weight is a measure of force of gravity
Weight formula
Uses the second law:
F = ma
W = mg or W = m·g
W = Weight (Force of gravity)
m = mass
g = acceleration due to Earth’s gravity which
is 9.8 m/s2
Example problem
• What is the weight of a 50 kg person on Earth?
weight
Mass = 50 kg
On earth acceleration
due to gravity =
9.8m/s/s
F=ma or
W = mg
W = 50 kg ∙ 9.8
𝑚
𝑠2
W = 490 NEWTONS (N)
11/13/13
• Exit Task
• We have learned a number of formulas in this
unit. Write down TWO and explain each of
the parts.
• Choices: speed or velocity, acceleration,
Newton’s 2nd Law, weight formula, universal
gravitation.
11/14/13
• Entry Task
• Look in the science textbook for a definition of
POWER.
• What is the everyday definition of power?
Today’s Agenda
• A few more notes on WORK and POWER
• Set up for Horsepower Lab
Work and Power
Work
• is the transfer of energy that results from
applying a force over a distance
– if nothing moves, no work was done
• unit of measurement is the Joule (J)
– used to be a Newton-meter (N•m)
– Eureka! Episode 8 - Work (4:57)
Work Formula
Example problem
• How much work is done when a 60 Newton dog is
lifted up7 meters?
work
Force = 60 N
Distance = 7m
Work = 60 N x 7m
Work = 420 N(m)
Work = 420 Joules
Work = Force x Distance
*Could have put N(m) instead of Joules– same thing.
Same distance means same work
(even if its easier)
3m
Work is the
same.
3m
This one would require less effort
Power
• how “fast” work is being done
• unit of measurement is the watt (W)
– James Watt, a Scottish engineer, invented the steam engine.
– James Watt explained power as the number of horses his engine
could replace
• Americans often use horsepower
– 1 horsepower = 746 watts
Power Formula
Example problem
• A motor does 500 Joules of work in 5 seconds. How
much power does the motor have?
500 𝐽𝑜𝑢𝑙𝑒𝑠
Power =
5𝑠
Power
Work = 500 joules
Time = 5 seconds
Power =
Power = 100 J/s
Power = 100 Watts
𝑊𝑜𝑟𝑘
𝑇𝑖𝑚𝑒
J/s is the same as a watt
Name
Human Horsepower
• GOAL:
– To calculate human horsepower when climbing stairs.
• Materials
– Stop watch, meter stick, student, calculator, stairs
• Procedure
–
–
–
–
–
Work in partners to collect data.
Record your weight in pounds.
Measure height of stairs.
Record time to climb the stairs
Calculate weight as force, work, power, and convert to
horsepower
Data Collection for Human Horsepower
Weight_______lbs.
Height of stairs _3.04__m
Time to climb stairs _______sec.
Using this data, you will calculate mass, weight
in newtons, work, power and horsepower
(American).
Calculations for Human Horsepower
• Convert your pounds to mass. We know that 1 pound
= 0.45 kg.
• Calculate your weight as a force. Use weight formula.
Units will be NEWTONS.
• Calculate the work to move your weight the height of
the stairs. Use work formula. Units will be JOULES.
• Calculate the power, or the work in a measured
amount of seconds. Use power formula. Units will be
WATTS.
• Convert power to horsepower. We know that 1
horsepower = 746 Watts
11/14/13
• Exit Task
• How is WORK related to POWER?
• (In Science class )
• REMINDER – Weight Practice Problems due
tomorrow!
11/15/13
• Entry Task
• Say Something Nice
Today’s Agenda
• Work time to complete Horsepower Lab
Calculations OR complete Weight Practice
Homework.
• During work time – I will be grading your
WEIGHT, WORK and POWER notes.
• END OF WORKTIME – calculate on-time HW
percentages per class.
• Trade and Grade Weight Practice Homework.
• Rest of class – watch Newton Video – answer
questions.
11/15/13
• Exit Task
• Trade and Grade
• Please turn in your Entry/Exit Task sheets
• You may turn in your Human Horsepower Lab
on Monday
11/18/13
Week of 11/18 to 11/22
• Entry Task
• List all the energy forms you know.
Today’s Agenda
• Review Horsepower Lab – turn in.
• Introduce Kinetic and Potential Energy with
notes.
• HOMEWORK: read pages 155-166. Answer
#1-5 on page 166. Due Thursday 11/21/13
Forms of Energy
2 Types:
Potential
Energy
is stored
energy.
Depends on what and
where the energy is
stored.
Kinetic Energy
is the energy of
motion.
Depends on what moves
and how it is moving.
Kinetic Energy
1. Mechanical: objects moving from one
place to another. Wind, water flowing,
cars moving, and rocks falling.
Kinetic Energy
2. Thermal: the internal energy in
substances - the vibration and movement of
atoms and molecules. More energy causes
the particles to move faster.
Kinetic Energy
3. Sound: the movement of energy through
substances by vibration of particles in
longitudinal waves (think slinky!).
Kinetic Energy
4. Electrical: the movement of current through a
conductor. Lightning, sparks, and electricity.
Kinetic Energy
5. Radiant: electromagnetic energy that travels
in transverse waves. Visible light, x-rays, radio
waves, etc.
*all EM waves move at the speed of light in a vacuum
*don’t need matter to travel!
Potential Energy
1. Chemical Energy: energy stored in the
bonds of atoms and molecules.
Petroleum, natural gas, coal, car batteries,
sugar, food.
Potential Energy
2. Mechanical Energy: energy stored by
the position of objects or by compressing
objects. Compressed springs, stretched
rubber bands, objects raised to a height
(gravitational).
Potential Energy
3. Nuclear Energy: energy stored in the
nucleus of an atom - the energy that
holds the nucleus together.
*nuclear fission results in the direct
conversion of mass to energy
KINETIC ENERGY
• depends on the object’s mass and velocity
• NOTE – velocity is squared so will have more
influence
Example problem
• How much kinetic energy is in a 5 kg ball with a
velocity of 7 m/s?
Kinetic Energy
Mass = 5 kg
Velocity = 7 m/s
Ek = ½ mv2
Ek = ½ mv2
= ½ 5kg (7)2
= 122.5
Joules
Gravitational Potential Energy Formula
gravitational PE = m · g · h
PE = Potential Energy
m = mass
g = acceleration due to gravity on earth (9.8 m/s2)
h = height
Example problem
• What is a gravitational potential energy of a 5 kg
brick 4 meters high?
PE
PE = (5kg)(9.8m/s/s)(4m)
= 196 Joules
Mass = 5 kg
Gravity = 9.8 m/s/s
Height = 4 m
PE = mgh
or kg(m/s2)(m)
Converting between mechanical KE and
gravitational PE
Law of Conservation of Energy
• energy cannot be created nor destroyed by
ordinary means
• in a closed system, it is not “used up” but just
converted to another form and therefore remains
constant
• we can never “run out” of energy
– however, may run out of the type we want the
most.
11/18/13
• Exit Task
• Explain the energy forms and conversions for a
battery operated flashlight.
• HOMEWORK: read pages 155-166. Answer #1-5
on page 166. Due Thursday.
11/19/13
• Entry Task
• Consider a pendulum swinging. What is the main
energy form at the peak of its swing?
• What is the main energy form at the lowest point
of its swing?
• HOMEWORK: read pages 155-166. Answer #1-5
on page 166. Due Thursday.
Today’s Agenda
• Pendulum Lab – a specific example of KE
converting to gravitational PE and back.
• Design Pendulum Lab
(Independent Variable) vs Time of one Pendulum
Swing
• Choose a Question
1. How does the length of the string affect the period
(time) of one pendulum swing?
2. How does added mass affect the period (time) of one
pendulum swing?
• Identify Variables
– Independent Variable
– Dependent Variable
• Hypothesis
• If the string is longer, then…because…
• If the mass is greater, then…because…
• Materials
– pendulum set up, string, meter stick, stop
watch, masses
• Procedure- student designed
1. Diagram and explain set-up
2. must have 3 different string lengths OR 3
different masses
3. 3 trials for each length or each amount of mass
4. Experimental control condition?
5. Explain how to measure the time of the period or
pendulum swing.
• Data Collection – student designed data table
– Rows for 3 string lengths OR 3 masses
– Columns for 3 trials and Average time calculations
11/19/13
• Exit Task
• Discuss with your group and choose your independent
variable. Write down on your exit task.
• Also, write down your hypothesis.
• HOMEWORK: read pages 155-166. Answer #1-5 on
page 166. Due Thursday.
11/20/13
• Entry Task
• List 3 controlled variables every team should
have in their pendulum lab procedure.
Today’s Agenda
• Approval for Pendulum Lab Design
– Procedure - Logical and simple steps to follow
(written in ALL comp books)
– Data Table – see my example
• Collect and Record Data
• Finished? Begin Graphing…LINE GRAPHS
– X axis independent variable
– Y axis dependent variable
Condition
Experimental Control
Condition
Condition 1
Condition 2
Condition 3
Trial 1
Trial 2
Trial 3
Average
Time
Time
Time
Time
11/20/13
• Exit Task
• Based on your data, answer your investigative
question:
1. How does the length of the string affect the period (time)
of one pendulum swing?
2. How does added mass affect the period (time) of one
pendulum swing?
• HINT: was the time longer, shorter or not affected?
• HOMEWORK: read pages 155-166. Answer #1-5 on
page 166. Due Thursday.
11/21/13
• Entry Task
• Explain the high and low data for your lab.
How will you use this data in your conclusion?
• Graphs of results
–
–
–
line graph
Y-axis – dependent variable
X-axis – independent
• Conclusion
• Restates and conclusively answers the investigative question (discusses
whether hypothesis was correct).
• Gives the range of data, including high data condition and low data
condition.
• Compares the high and low data and explains how the trends support the
conclusion.
• Further Investigative Question:
– What independent variable would you investigate
next?
– identify two Weaknesses for your lab as a whole
– suggest specific Improvements for your lab as a
whole
11/21/13
• Exit Task
• We know that all objects in free-fall accelerate
at a rate of 9.8 m/s/s REGARDLESS of mass.
• Use this information to explain why it makes
sense that added mass had no affect on the
time of swing.
11/22/13
• Entry Task
• Say Something Nice
Today’s Agenda
• Study Guide for Unit Test.
11/22/13
• Exit Task
• Trade and Grade
• Please turn in your exit task sheets
11/25/13
Week of 11/25 to Wed 11/27
• Entry Task –
•
•
•
•
•
NO Written ENTRY/EXIT TASKS THIS WEEK!!
Tuesday and Wednesday – TESTING.
Discussion Questions:
What did you study over the weekend?
What will you study tonight?
Today’s Agenda
• Individual Work time on Study Guide.
• Please remain at your seat quietly working.
11/25/13
• Exit Task
•
•
•
•
Discussion Questions:
What will you study tonight?
Which items on the study guide confuse you?
What questions do you have?
11/26/13 and 11/27/13
• Entry Task
• Prepare for test:
• You will need a pencil.
• All other belongings under your desk.
TESTING
•
•
•
•
•
Remain silent and seated.
RAISE YOUR HAND IF…
You have a question.
Your test is complete.
You need a sharpened pencil or eraser.