Transcript Week 4_Motion and Force

Motion BOOT CAMP
09/9/11
Catalyst (A science term, a substance that starts a reaction. We start our class with a
catalyst!)
New way of doing a catalyst and getting class started:
--Will be CHECKED at the end of class. You need to have it completed BEFORE you can leave.
--In order to leave class, you need a stamp from me.
--I will only stamp your notebook if I see you doing your catalyst in the first 5 minutes of
class only (right after the bell rings, the time begins).
1. Solve the following problems:
1. Find the average speed of a car that travels 30 kilometers in 15
minutes. Write the formula you use, show all of your work, and
use the proper units.
2. What is the acceleration of a soccer ball that is kicked from
rest and takes 5 seconds to reach a velocity of 15 m/s? Write the
formula you use, show all of your work, and use the proper units.
3. An object moves 3 cm to the left and then 5 cm to the right.
What is the total distance traveled? What is the displacement?
Show all your work and use the proper units!
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Motion BOOT CAMP
09/9/11
Catalyst
1. Speed = d/t d = 30 km; t = 15 min
s = 30 km/15 min = 2 km/min
2. Acceleration = (Vf – Vi)/t
Vf = 15 m/s;
Vi = 0 m/s; t = 5 s
a = (15 m/s – 0 m/s)/5 s = 15 m/s/5 s = 3
m/s2
3. Diagram. Total distance traveled = 3 cm +
5 cm = 8 cm
Displacement = 2 cm (based on diagram)
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Motion BOOT CAMP
09/9/11
Announcements
1.Notebook pop quizzes and checks:
Maintain your notebook! Use the absentee
notebook or website if you were absent!
2.Test is now on TUESDAY!
3.Quiz re-takes = TODAY!
4.Lab Write-up Homework due TUESDAY!
5.Norms on HW questions
1.“I don’t get it” isn’t a question
2.ASK questions, start somewhere
3.Think critically! Break it down!
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ALSO,
My number is 203-560-8146 and it is correct on
the website. Please make sure you are dialing the
right number and ALWAYS leave a message or else
I can’t call you back!
If you send me an email, I may not get to it until
later…be sure to check before you go to bed and
when you wake up. I WILL respond to your email,
it just may not be immediately!
NEW TABLE SET-UP!!
Take note of your table number and
seat letter!
We will be using these set-ups for
Think-Write-Pair-Shares and other
partner/group activities!
NEW POLICIES!!
Index cards: I will put a tally mark
on the back if I call on you and you
are off task or unfocused. A daily
report will be emailed to Mr. Gomez
Pencils: You must ASK before you
exchange! Only during catalyst, no
other time during class. See rule #3.
Motion BOOT CAMP
09/9/11
Stopping on a Dime Lab Write-Up (questions from the Word file online)
I will use my lab worksheet and the data table on
the back to answer these questions!
1. Calculate the average speed of the student who ran the 24 ft. course the fastest.
2. Multiply the speed of the fastest student (calculated in the previous question) by the
slowest reaction time listed in your data table. Why would you be interested in this
product?
3. Add the distance calculated in the previous question to the longest stopping distance in
your data table. What does this total distance represent?
4. Explain why it is important to use the fastest speed, the slowest reaction time, and the
longest stopping distance in your calculations.
5. What other factors should you take into account to get results that apply to a real
basketball court?
6. Suppose you calculate that the distance from the out of bounds line to the wall of the
basketball court is too short for safety. Write a proposal to the school that describes the
problem. In your proposal, suggest a strategy for making the court safer. This proposal
should be a separate paragraph in your lab write-up.
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What’s our problem??
The school will put in a new
basketball court in a small area
between 2 buildings. Safety is an
important consideration in the
design of the court. What is the
distance needed between an out-ofbounds line and a wall to that a
player can stop before hitting the
wall?
Motion BOOT CAMP
09/9/11
Stopping on a Dime Lab Write-Up (questions from the Word file online)
I will use my lab worksheet and the data table on the back to answer these
questions!
Paragraph Outline
1st paragraph = What did we do in the lab? How did we calculate
stopping distance, running time, and reaction time? What problem
are we trying to solve?
2nd paragraph = Question 1.
3rd paragraph = Question 2.
4th paragraph = Question 3.
5th paragraph = Question 4.
6th paragraph = Question 5.
7th paragraph = Question 6.
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Motion BOOT CAMP
09/9/11
Stopping on a Dime Lab Write-Up (questions from the Word file online)
I will use my lab worksheet and the data table on
the back to answer these questions!
1. Calculate the average speed of the student who ran the 24 ft. course the
fastest.
2. Multiply the speed of the fastest student (calculated in the previous question)
by the slowest reaction time listed in your data table. Why would you be
interested in this product?
3. Add the distance calculated in the previous question to the longest stopping
distance in your data table. What does this total distance represent?
4. Explain why it is important to use the fastest speed, the slowest reaction time,
and the longest stopping distance in your calculations.
5. What other factors should you take into account to get results that apply to a
real basketball court?
6. Suppose you calculate that the distance from the out of bounds line to the wall
of the basketball court is too short for safety. Write a proposal to the school
that describes the problem. In your proposal, suggest a strategy for making the
court safer. This proposal should be a separate paragraph in your lab write-up.
8R
Motion BOOT CAMP
09/9/11
Stopping on a Dime Lab Write-Up (questions from the Word file online)
I will use my lab worksheet and the data table on the back to answer these questions!
Paragraph Outline
Explanation of Questions
1. What is the equation for average speed? Which numbers did
you use? What is your answer with units?
2. What is the slowest reaction time? What is speed multiplied by
time? What does this number tell you?
3. What is the longest stopping distance? Convert inches to feet.
This entire distance is total stopping distance.
4. We want to make sure that ALL basketball players can stop in the
distance we calculate!
5. Think of a real basketball court…what are some things that
would affect how quickly a player can stop?
6. Write to the people building the basketball court. Explain why it
is important to have a big enough stopping distance. Tell them
what you think the stopping distance should be (your answer to
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#3) and why.
Motion BOOT CAMP
09/9/11
Stopping on a Dime Lab Write-Up (questions from the Word file online)
I will use my lab worksheet and the data table on the back to answer these questions!
Paragraph Outline
Explanation of Questions
Homework
--If you feel your lab write-up fully answers all the questions,
you may hand it in at the end of class.
--If you would like to re-write your lab write-up, you may take
tonight to re-write it and hand it in TOMORROW.
--Computer lab will be open before school tomorrow (see Mr.
Gonzalez). Ms. Cruz for printing ONLY early in the morning
before school.
--I will NOT accept anything on a flash drive.
--I will accept handwritten work that is 2 pages FRONT AND
BACK. It will be returned and marked as late if I cannot read it.
Re-write lab write-up.
Due
TUESDAY.
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MOTION BOOT CAMP!!!!
Get ready to work.
09/9/11
MOTION BOOT CAMP!!!!
Phase 1--To be done in pairs:
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1. When is an object moving?
2. What is the equation for speed?
3. What is velocity?
4. What are the 3 types of acceleration?
5. What does the slope of a distance vs.
time graph represent?
6. What is a reference point?
7. What is the equation for acceleration?
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MOTION BOOT CAMP!!!!
Phase 1--To be done in pairs:
09/9/11
1. When the distance between it and another
object is changing
2. Speed = distance/time
3. Speed/magnitude in a given direction
4. Increasing speed, decreasing speed, and
changing direction
5. Speed
6. A point used for comparison to tell whether an
object is in motion
7. Acceleration = (Vf – Vi)/t
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MOTION BOOT CAMP!!!!
Phase 2--To be done individually:
09/9/11
1. When you know both speed and
direction, what do you know?
2. If a bicyclist travels 30 km in 2 hours,
what is her average speed?
3. A car travels 100 km the first hour of the
trip. The car continues to travel for 2 more
hours and travels 200 km. What was the
average speed of the car for the trip?
4. Why is the moon accelerating?
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MOTION BOOT CAMP!!!!
Phase 2--To be done individually:
09/9/11
1. Velocity
2. S = d/t, d = 30 km; t = 2 hrs, s =
30km/2hrs = 15 km/hr
3. S = d/t, d = 100 km + 200 km = 300 km;
t = 1hr + 2hrs = 3hrs, s = 300 km/3hrs =
100km/hr
4. Because it is changing direction
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Review and Lesson 3.1 The Nature of Force
Catalyst (Remember to get your STAMP!)
09/9/11
1. What is an object doing when either its
speed or direction is changing?
2. Seated passengers are on a boat that is
moving down a river. Give examples of 2
reference points – one that tells me the
passengers are moving and one that tells me
the passengers are not moving.
3. If a train traveling at 30 m/s brakes to a stop
in 1 minute, what is the magnitude of its
acceleration? Hint: WATCH OUT FOR UNITS!!!
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Review and Lesson 3.1 The Nature of Force
Catalyst (Remember to get your STAMP!)
09/9/11
5. It is accelerating.
6. Compared to people on shore, the
passengers are moving. Compared to
the boat, the passengers are NOT
moving. f
7. A = (Vf –Vi)/t, Vf = 0 m/s; Vi = 30
m/s; t = 1 min = 60 sec, a = (0 m/s –
30 m/s)/60 s = -30 m/s/60 s = -.5 m/s2
magnitude of acceleration = .5 m/s2
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Phase 3--ON A SEPARATE SHEET OF PAPER!
Last Name, First Name
1. When an object’s distance from another
Period #
object is changing (write the letter AND the
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words),
Unit 2 Quiz Retake
a. it is in motion.
b. it is moving at constant speed.
4. The statement that the motion of a
c. it has a high velocity.
hurricane is 20 kilometers per hour in an
d. it is accelerating.
easterly direction is a description of the
hurricane’s ____________________. (Just
2. The moon accelerates because it is (write write the word to fill in the blank for your
the letter AND the words)
answer)
a. in a vacuum in space.
b. continuously changing direction.
5. A roller coaster is moving at 10 m/s at the
c. a very large sphere.
top of a hill and 22 m/s at the bottom of the
d. constantly increasing its speed of orbit.
hill two seconds later. Find the acceleration.
You must show all of your work, the formula
3. A car travels 85 km in the first hour of a
you used, and use the proper units.
trip. The car continues to travel for 2 more
hours and travels 200 km. What was the
average speed of the car for the trip? (Write
the letter AND the words)
a. 39 km/h
b. 95 km/h
c. 115 km/h
d. 285 km/h
On one side of your index card, please write NEATLY:
Your first and last name
Your email address
Your parent’s first and last name
Their phone number
Their email, if they have one
When you are done, have 1 person at your table
collect all the cards and bring them to me.
Review and Lesson 3.1 The Nature of Force
Class Reading p. 354
Graphing Motion
Distance vs. Time
Speed vs. Time
X-axis (units)
Run
Time (seconds)
Time (seconds)
Y-axis (units)
Rise
Distance (meters)
Speed (m/s)
Slope represents…
(units)
Rise/Run
Speed (m/s)
Acceleration (m/s2 )
Straight line means…
Constant speed
Constant acceleration
Curved line means…
Accelerating
N/A
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09/8/11
Review and Lesson 3.1 The Nature of Force
09/8/11
Demo! Then…
CATALYST
What caused a change in the skateboard’s
velocity?
The change in velocity is caused by…
…a push or a pull, which is also known as a
force!
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Review and Lesson 3.1 The Nature of Force
09/8/11
NEW Unit 3: Introduction to Forces!
Vocabulary: Force, Newton, net force
A force is described by its magnitude and by the
direction in which it acts.
Force is measured in Newtons. Example = It takes
about 1 N of force to lift a small apple.
Net force = combination of all forces acting on an
object
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Review and Lesson 3.1 The Nature of Force
09/8/11
Think-Write-Pair-Share
1. What is an example of a “push” force? What is
an example of a “pull” force?
A push force would be kicking a soccer ball. A pull
force would be tug of war.
2. If there are multiple forces acting on an object,
why is the direction AND magnitude important?
Hint: Think of net forces!
You need to know the direction and magnitude of
all the forces to combine them and determine
which ones cancel out and which ones add
together. This is the net 9L
force!
Review and Lesson 3.1 The Nature of Force
Force Diagrams and Calculating Net Force
Examples:
Same magnitude and direction
Unequal magnitude, opposite direction
Equal magnitude, opposite direction
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09/8/11
Review and Lesson 3.1 The Nature of Force
09/8/11
Exit Slip
Draw your own force diagram and calculate the net
force.
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