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Day 5 – Quiz day
Mr. Lambert
Integrated Science 1A
Trimester 2, 2014
+ Bell Ringer
Come
up with a scenario for the
following distance-time graph:
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Agenda
1.
Quick review
2.
QUIZ
3.
Exit Slip
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Learning Targets
On your Bell Ringer
Sheet, write the
following:
We will define frames
of reference and
relate them to speed
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Reference frame
Speed
is relative!
This
means that how fast/slow an object moves
depends on the watcher’s “point of view”
In
physics, a “point of view” is called
Frame of Reference (FOR)

Frames of reference

https://www.youtube.com/watch?v=Y3xn
Vti7htQ
Practice Problem #1
A boy rides his skateboard down
the sidewalk at 3m/s north.
1.
How fast is the boy moving
relative to someone standing
on the sidewalk?
2.
What is the boy’s speed
relative to the skateboard?
Practice Problem #2
Sabrina is riding her bicycle at 5 mph while
holding a tennis ball. A boy is running in the
opposite direction at 5 mph.
1.
2.
Sabrina drops the ball. What is the speed of
the ball relative to the boy standing on the
sidewalk?
What is the speed of Sabrina relative to the
boy?
Practice Problem #3
Train pulls into station at 40m/s. As the
train moves, a passenger walks at 2m/s
towards the front of the train.
1.
What is the speed of the walking
passenger relative to the
passengers on the train?
2.
What is the speed of the walking
passenger relative to the people
waiting on the platform?
Videos!

Mythbusters relative motion


https://www.youtube.com/watch?v=qQVDA
Mzo4mE
Relative motion projectile

https://www.youtube.com/watch?v=NO9c9E
M39GM
Practice Problem #3
Sam is standing in the back of a pick-up truck traveling at
35m/s. He throws apples backwards off the truck as it moves.
Everyone knows Sam can throw apples at a speed of 12m/s
every time.
1.
2.
3.
What is the speed of the apple before it is thrown
relative to Sam?
What is the speed of the apple as it is thrown relative to
Sam?
What is the speed of the apple as it is thrown relative to
Sam’s friend across the street?
Practice Problem #4
You are pulling your little brother in his red wagon. He has a
ball, and he throws it straight up into the air while you are
pulling him forward at a constant speed.
1.
What will the path of the ball look like to your little brother?
SKETCH IT!
2.
A little girl is standing on the sidewalk watching. What will the
path of the ball look like to her? SKETCH IT!
3.
If your brother throws the ball forward at a velocity of 2.0m/s
while you are pulling the wagon at a velocity of 4.0m/s, at what
speed does the girl see the ball move?
 Groups
 Complete
handout
 http://dev.physicslab.org/Docum
ent.aspx?doctype=5&filename=K
inematics_RelativeVelocity.xml
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Exit Slip
A quarterback throws a football down the field at 50
mph. His receiver is running down the field at 20
mph.
1.
How fast is the football moving from your point of
view (as you are sitting in the bleachers)
2.
How fast is the football moving from the point of
view of the receiver?
3.
Do you think they are the same?