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Why go into physics? Go to www.physics.orgFind 3 areas that interest youList 2 jobs that you could have in
that areaGoogle 1 of the jobs and try and
find out how much that job makes
Physics effects every moment of your life! ____________________________________________________________________________________________________
CH. 2 Motion Keep on truckin
What is motion? Motion is a change of position of an
object.
A reference point must be specified in order to determine an object's position
What is Speed? Rate—any change over timeSpeed—the distance an object
travels per unit of time.
fastest
Graphs! Speed= distance time graphs
The slope of a line (steepness) on a distance-time graph is equal to the speed. Shallow slope is slower than steep slope
The Comic Book of Science
Draw this on your paper!
slower
faster
Time (seconds)
Dis
tance
(m
ete
rs)
Standing stillX-axis
Y-axis
Distance Time GraphsWhat information is
recorded on the x-axis?
How many minutes does each line represent?
In what units is distance measured on the graph?
The graphs represent three swimmers, What does the slope of the lines tell you about the swimmers?
Which swimmer swam the fastest?
Which swimmer stopped for 10 minutes?
How far did the blue swimmer travel in 15 minutes?
What is the difference in distance traveled between the red and green swimmer?
Warm-up 1/31/11Review questions: What is one
thing that is good for the brain to learn?
Teach the teacher questions: What is your favorite dessert?
Do you have a cell phone? Does your cell phone have a camera?
What are the fastest animals (mph)?Cheetah 70Pronghorn antelope 61 Lion 50 Thomson's gazelle 50 Wildebeest 50 Springbok 50 Quarter horse 47.5 Cape hunting dog 45 Elk 45 Coyote 43
Calculating Speed• The speed of an object can be
calculated from this equation: Speed = Distance
Time
S=D/T
When working equations◦Write the formula◦Plug in the values for each known◦Calculate the answer◦Write the answer and a unit
D
S T
multiply
divide
Average & Instantaneous Speed
Average speed—the total distance traveled divided by the total time of travel.
Instantaneous speed—the speed at a given point in time.
Warm-up 2/1/11Review questions: list everything
you need to make a distance time graph and/or how do we calculate speed?
Teach the teacher questions:
What would be your dream vacation?
VelocitySpeed describes
only how fast something is moving.
Velocity—includes the speed of an object AND the direction of its motion
Example:
Example: a race car has a constant speed of 100km/hr around an oval track.◦The speed remains constant, but the velocity changes.
AccelerationAcceleration—the rate of change of
velocity.◦The change in velocity over time◦acceleration = change in velocity
time
When something speeds up, it has a positive acceleration
When something slows down, it has a negative acceleration.
Change in velocity= vfinal –Vstart
Acceleration= vfinal –Vstart
Time
Units= distance (meters, miles)/sec2
Application of speed, velocity, and acceleration Sports Science
Binder Sections Warm-upNotesLab or Projects Unfinished work
Put as many warm-ups that will fit on a page as possible
Vocab Sheet Vocab Poster needs: Word,
definition, and picture (depending on the word).
MUST BE BIG ENOUGH TO READ FROM ACROSS THE ROOM!
vocab: Motion, speed, acceleration, velocity, distance time graph, rate, speed, reference point, neurons, 6 keys
Kinetic energy http://www.wimp.com/
kineticsculpture/
Warm-up 2/4 Review: list any of the six keys
you can think of and anything from speed or velocity?
Question: list any cartoons you have seen more then once…family guy, sponge bob ect.
Warm-Up 2/8/11
Review questions: Draw the distance, speed, time triangle and list any professions that might use speed, velocity, and acceleration
Teach the teacher questions:
What were your feelings on the super bowl
Practice Acceleration Problems
1. A skater increases her velocity from 2.0 m/s to 10.0 m/s in 3.0 seconds. What is the skater’s acceleration?
Looking forAcceleration of the skaterGivenBeginning speed = 2.0 m/sFinal speed = 10.0 m/sChange in time = 3 seconds
V
A T
Divide->
multiply
SolutionA=10.0 m/s – 2.0 m/s = 2.7m/s2
3s
The acceleration of the skater is 2.7 meters per second per second.
Negative vs. Positive AccelerationAn object speeds up if
its acceleration is in the direction of its motion.
An object slows down if its acceleration is opposite to the direction of its motion.
Velocity vs Time Graph of Positive Acceleration
Calculating Negative AccelerationA skateboarder is moving at 3 m/s and comes to a stop in 2 s. What is the acceleration?a = (vf – vi) = (0 m/s – 3 m/s) =
-1.5 m/s2
t 2 s
The skateboarder slowed down, so the acceleration is negative.
Velocity vs Time Graph of Negative Acceleration
Zero AccelerationWhen an object has a constant velocity, the acceleration is zero.
An Object Changing Acceleration
ACCELERATION ANIMATIONObserve the animation of the three cars below. Which car or
cars (red, green, and/or blue) are undergoing an acceleration? ◦ Study each car individually in order to determine the
answer.
Now that you've answered the first question correctly, try this one: which car (red, green, or blue) experiences the greatest acceleration?
As a final test of your understanding, consider the position-time graph at the right.
Each one of the three lines on the position-time graph corresponds to the motion of one of the three cars.
Match the appropriate line to the particular color of car.
Warm-Up 2/10/11Review: List all the different units
you can think of for time, distance, speed/velocity, acceleration.
Teacher the Teacher: What is
your favorite soda or flavored drink?
See acceleration happening
Flash Card
On the front write:
Motion
On the back write:
a change of position of an object.
Flash Card
On the front write:
Reference Point
On the back write:
Determines an object’s position and if motion happened
Flash Card
On the front write:
Average Speed
On the back write:
the total distance traveled divided by the total time of travel
Flash Card
On the front write:
Acceleration
On the back write:
The change in velocity over time (draw triangle)
Flash Card
On the front write:
Instantaneous Speed
On the back write:
the speed at a given point in time
Flash Card
On the front write:
Velocity
On the back write:
The speed and direction of an object
Flash Card
On the front write:
Slope of graph
On the back write:
D vs T graph=speed
V vs T graph=acceleration
Steeper slope=more speed or acceleration
Accelerometer Observations 1. What happens when you walk
slowly at the same rate?
2. What happens when you speed up? When you slow down?
3. What happens when you stop?
Warm-up 2/14/11Review: List all of the flash card
words you can remember. Use resources.
Teach the Teacher Question: If I could give you a gift card to any store in the mall for $100, which store would you want?
Failure video
