1. Science 10: Physics
1. Motion
2. Work & Energy
3. Efficiency

2. Motion
Motion is a change in position of an object with respect to time
Uniform Motion: describes an object that is travelling at a constant rate of motion in a straight line.
It is nearly impossible to achieve uniform motion in our everyday lives
Even driving with cruise control on a straight highway there are factors which slow and speed the car up... Wind resistance, friction of the tires on the road, which make the engine work harder varying the rate of motion slightly.

3. Motion Kinematics is the mathematical description and study of motion.
Galileo was among the first to study motion experimentally, systematically, and mathematically. Einstein called Galileo the “Father of modern science” for his work.

4. Motion involves measuring aspects such as:
speed or velocity
distance or displacement
time
acceleration
direction

5. Vector and Scalar Quantities
Scalars only have magnitude (a number)
Vectors have both magnitude and direction
Direction may be defined as north/south or up/down or +/-

6. Physics needs vectors.
But What is a vector?
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7. Physics
Phun
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8. Physics
Phun
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10. Physics
Phun
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11. The word is used everywhere!
Physics
Phun
The word is used everywhere!
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12. Vectors have magnitude and direction
But what does the word “vector” mean in physics?
Vectors have magnitude
and direction
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13. Scalars have magnitude only.
Vectors have magnitude and direction.
Scalars have magnitude only.
e.g., velocity, displacement, acceleration
e.g., speed, time, distance
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14. Arrows can be used to represent vectors.
Arrow length is magnitude.
Arrow point is direction.
North
10 m, east
5.0 m, east
6.0 m, west d
A vector symbol may have an arrow over top as a reminder that it is a vector.

15. Vector Notation d d
Some teacher may want the vector arrow over the symbol at all times. I don’t I see it as a reminder that the symbol represents a vector. Cluttering the equations with arrows and absolute value signs make it more difficult for the students.
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16. Sign Conventions East – positive West – negative North – positive
South – negative
Right – positive
Left - negative
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17. Direction ? How else can you report the direction of a vector ?
Cardinal direction and bearings
N (0°)
E (90°)
W (270°)
S (180°)
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18. Practice Vector A Vector B 6m 2m 10m 8m Vector D Vector C
30° 2m
10m
40° 8m
Vector D
Vector C
Remember !! Always give a direction for vectors 
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19. Motion Origin a point of reference.
Position is the distance and direction away from a reference point.
Displacement is a vector that describes an object’s change in position. Δd

20. Practice The car travelled 300 km. distance
vector
scalar
displacement
The car travelled 300 km, west.

21. The car was travelling 100 km/h.
speed
The car was travelling 100 km/h.
vector
scalar
velocity
The car was travelling 100 km/h to the west.
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22. Distance and speed are scalars.
Displacement and velocity are vectors.
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25. What about the units ?  500m = ? km 40hr = ? mins = ? s
***When doing calculations make sure you look at your units***
500m = ? km
40hr = ? mins = ? s
8.75km = ? m = ? cm
7923s = ? Hr
What about m/s  km/h
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26. Page 101
5. A German Shepherd ran 10 m north and then 25 m south. Determine the
a. distance travelled by the dog.
b. dog’s displacement relative to its starting point.
north
10 m, north
25 m, south
d = d d2
= 10 m m
= 15 m, south
a. The dog travelled a distance of 35 m.
b. The dog’s displacement relative to its starting point is 15 m, south.
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27. Page 101
6. A construction crane lifts a concrete block 9.0 m directly up and then lowers it 6.0 m directly downwards and stops. Determine the
a. total distance the block travelled.
b. block’s displacement relative to the ground.
a. The block travelled 15.0 m.
b. The block’s displacement relative to the ground is 3.0 m above the ground.
p. 100 #1 - 7 Do
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28. Lesson 2 – Speed and Velocity
Speed is a scalar quantity that describes how fast an object is moving.
Velocity is a vector that describes an object’s change in position during time
Where:
v is speed or velocity, v
d is distance(speed) or displacement(velocity) d
t is time

29. Example
A person walks 10.0m away from a bus stop in 5.00s. What is the average speed of the person?
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30. Example
A dog runs 20 m [N] chasing a ball and then turns around and runs 15 m [S] towards its owner. It takes the dog 12.5s. What is the average speed and velocity of the dog?
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31. Page 102
9. The cheetah is the fastest land animal. Determine a cheetah’s speed if it can travel 150 m in 5.0 s.
The cheetah’s speed is 30 m/s.
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32. i. List the given and required information (draw a diagram)
Problem Solving
i. List the given and required information (draw a diagram)
ii. Write down the formula(e)
iii. Isolate the desired variable (algebra)
iv. Substitute the variables with numbers including the units
v. Solve for the answer
vi. Write the answer in a sentence (including significant digits and appropriate units)
p. 102 #8 - 10 Do
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33. Page 103
11. A car travels at 22 m/s for a time of 128 s. Determine the distance travelled.
The car travels 2.8 km.
Show answer in scientific notation or change the units to km for proper significant digits.
The car travels 2.8 x 103 m.
p. 103 # Do
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34. Motion Quiz 1
Show all work. Include units and answer in a sentence with the appropriate amount of significant digits.
1. Determine the speed of an airplane if it travels 200 m in a time of 3.1 s.
2. A car travels 22 m/s for a time of 128 s. Determine the distance the car travelled.
3. A bird flies 100m [N] then heads 28m [S] for a time of 4 mins. Determine the birds velocity in m/s and km/h
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35. Speeding up or slowing down.
2. Non-Uniform Motion
Page 107
 Notes:
Acceleration is a vector that describes an objects change in velocity over time.
Speeding up or slowing down.
accelerated motion can be determined using: or
a = ∆v ∆t
N.B., Final and initial do not have to be actually start and stops.
Where:
a is acceleration (m/s2)
vf is final speed or velocity (m/s)
vi is initial speed or velocity (m/s)
t is time (s)
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36. m/s m/s2 Velocity Acceleration 2. Non-Uniform Motion Page 107
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37. Positive and Negative acceleration
Vector Directions
Positive and Negative acceleration
Page 107 v a
Speeding up v a v
Slowing down a v a
p. 108 #1 - 7 Do
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38. Positive and Negative A
Positive Acceleration Occurs in Two Ways
When an object’s velocity is increasing in a positive direction.
When an object’s velocity is decreasing in a negative direction
Negative Acceleration Occurs in Two Ways
When an object’s velocity is decreasing in a positive direction
When an object’s velocity in increasing in a negative direction
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39. i. List the given and required information (draw a diagram)
Problem Solving
i. List the given and required information (draw a diagram)
ii. Write down the formula(e)
iii. Isolate the desired variable (algebra)
iv. Substitute the variables with numbers including the units
v. Solve for the answer
vi. Write the answer in a sentence (including significant digits and appropriate units)
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40. Example
A racing car accelerates from rest to a speed of 200km/h (55.6m/s) [E] in 6.00s. What is the acceleration of the car.
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41. Solution
a = vf - vi ∆t
a = 55.6m/s – 0.00m/s
6.00s
= 9.27m/s2
The car’s velocity is increasing at the rate of 9.27m/s2 [E] (This is positive acceleration)
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42. Example
A rocket accelerates from rest at a rate of 500 m/s2 [up] to a speed of m/s [up]. How long does it take to reach top speed ?
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43. Solution The time it takes for the rocket ro reach top speed is 300 s
t = vf - vi a
t = m/s[up] – 0.00m/s
500m/s2 [up]
= 300s
The time it takes for the rocket ro reach top speed is 300 s
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44. Page 111
13. Use the acceleration equation and isolate each variable. You will have a total of four different versions. t vf vi
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45. m/s m/s2 Constant Velocity Acceleration Page 107 p. 109 #8 - 14 Do
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46. Page 108
3. A sprinter reaches a speed of 10.9 m/s in a time of 5.2 s. Calculate the magnitude of his acceleration if he started from rest.
vi = 0
The sprinter’s acceleration is 2.1 m/s2.
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47. Page 110
9. A car accelerates to the north at 4.5 m/s2 for a time of 2.54 s. Calculate its final velocity if its initial velocity is 12.3 m/s to the north.
The car’s final velocity is 24 m/s to the north.
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48. Motion Quiz 2
Show all work. Include units and answer in a sentence with the appropriate amount of significant digits.
1. Calculate the magnitude of the acceleration for an object that takes 2.51 s to increase its speed from 3.5 x 102 m/s to 6.6 x 103 m/s.
2. A car accelerates to the north at 4.5 m/s2 for a time of 2.54 s. Calculate its final velocity if its initial velocity is 12.3 m/s north.
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49. Motion Quiz 2
Show all work. Include units and answer in a sentence with the appropriate amount of significant digits.
1. Calculate the magnitude of the acceleration for an object that takes 1.52 s to increase its speed from 3.5 x 103 m/s to 6.6 x 104 m/s.
2. A car accelerates to the south at 6.5 m/s2 for a time of 1.54 s. Calculate its final velocity if its initial velocity is 10.3 m/s south .
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50. Graphing Linear Motion
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51. Graphing Motion Graphs can be used to communicate motion.
Aspects of motion include:
time
displacement
velocity
acceleration
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52. Motion Motion may communicated using words, equations or graphs.
Page 2
Motion may communicated using words, equations or graphs.
Motion
Words
Equations
Graphs
We must be able to translate between the three different modes of communications.
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53. sketch graphs from written descriptions
vs.
Plotting a Graph
Sketching a graph
We must be able to:
sketch graphs from written descriptions
write descriptions from graphs
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54. Uniform Motion Graphs
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55. Questions  What is a distance(position)-time graph?
What is a speed(velocity)-time graph?
How do features on one graph translate into features on the other?
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56. D-T Graphs Show an object’s position as a function of time.
x-axis: time
y-axis: position
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57. We only use quadrant I and II for our motion graphs in Science 10.
Quadrants of the Cartesian Coordinate System + II I
Time is almost always on the x-axis +
We only use quadrant I and II for our motion graphs in Science 10.
III IV
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58. D-T Graphs
Imagine a ball rolling along a table, illuminated by a strobe light every second.
You can plot the ball’s position as a function of time.
0 s
1 s
2 s
3 s
4 s
5 s
6 s
7 s
8 s
9 s
10 s
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59. 1 2 3 4 5 6 7 8 9 10
time (s)
position (cm)
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60. What are the characteristics of this graph?
Straight line, upward slope
What kind of motion created this graph?
Constant speed 1 2 3 4 5 6 7 8 9 10
time (s)
position (cm)
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61. Each type of motion has a characteristic shape on a D-T graph.
Constant speed
Zero speed (at rest)
Accelerating (speeding up)
Decelerating (slowing down)
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62. Constant speed is represented by a straight diagonal segment on the D-T graph.
time (s)
pos. (m)
Constant speed in positive direction.
time (s)
pos. (m)
Constant speed in negative direction.
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63. zero speed is represented by a straight, flat segment on the P-T graph.
time (s)
pos. (m)
A horizontal segment means the object is at rest.
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64. Displacement – time graphs
Time is always on the x-axis
Slope = velocity
Stationary
Constant velocity
time
displacement
time
displacement
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65. Example
Identify the graph that shows an object furthest from the reference point. a. b.
time
displacement
time
displacement
Furthest from reference
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66. Identify the graph that represents the faster object.
Example
Identify the graph that represents the faster object. a. b.
time
displacement
time
displacement
Faster
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67. Negative slope = negative direction
Example
Identify the graph that shows an object travelling to the left (assuming right is positive). a. b.
time
displacement
time
displacement
Travelling to the left
Travelling to the right
Negative slope = negative direction
Positive slope = positive direction
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68. Example C D B A E 4 moving to right, slower 3 moving to left, faster
Time (s)
Displacement (m) 2 4 1 3
moving to right, slower
moving to left, faster A B C D E
stationary
stationary
moving to right
The teacher can walk the motion described by the graph while explaining the graph.
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69. The slope of a D-T graph is equal to the object’s velocity in that segment.
change in y
change in x
(30 m – 10 m)
(30 s – 0 s)
(20 m)
(30 s)
slope = 0.67 m/s
time (s)
position (m) 10 20 30 40 50
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70. V-T Graphs
A velocity-time (V-T) graph shows an object’s velocity as a function of time.
A horizontal line = constant velocity.
A straight sloped line = constant acceleration.
Acceleration = change in velocity over time.
Positive slope = positive acceleration.
Not necessarily speeding up!
Negative slope = negative acceleration.
Not necessarily slowing down!
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71. A horizontal line on the V-T graph means constant velocity.
time (s)
velocity (m/s) N S
Object is moving at a constant velocity North.
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72. A horizontal line on the V-T graph means constant velocity.
time (s)
velocity (m/s) N S
Object is moving at a constant velocity South.
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73. If an object isn’t moving, its velocity is zero.
time (s)
velocity (m/s) N S
Object is at rest
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74. If the V-T line has a positive slope, the object is undergoing acceleration in positive direction.
If v is positive also, object is speeding up.
If v is negative, object is slowing down.
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75. V-T graph has positive slope
time (s)
velocity (m/s) N S
Positive velocity and positive acceleration: object is speeding up!
time (s)
velocity (m/s) N S
Negative velocity and positive acceleration: object is slowing down.
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76. If the V-T line has a negative slope, the object is undergoing acceleration in the negative direction.
If v is positive, the object is slowing down.
If v is negative also, the object is speeding up.
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77. V-T graph has negative slope.
time (s)
velocity (m/s) N S
Positive velocity and negative acceleration: object is slowing down,
time (s)
velocity (m/s) N S
Negative velocity and negative acceleration: object is speeding up! (in negative direction)
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78. Slope = acceleration Area = displacement Page 99
Velocity - time graphs for Uniform Motion
Slope = acceleration
Area = displacement
time
velocity a. b.
time
velocity
Constant velocity
Acceleration
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79. How a d-t graph relates to a v-t graph.
Compare:
How a d-t graph relates to a v-t graph. a.
time
velocity b.
time
displacement
10 m/s
If slope = 10 m/s
Slope = speed
Slope = acceleration
Both graphs describe the same motion – constant velocity.
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80. Compare:
Note that the two graphs below look identical but mean totally different things.
time
displacement
velocity a. b.
Uniform motion
(constant velocity)
Non-uniform motion
(acceleration)
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81. Page 104 19. Use the graph to determine velocity. y2 – y1 Slope =
x2 – x1
Slope =
10.0 m – 4.0 m
9.0 s – 0.0 s
10.0, 9.0
10.0
Slope =
0.67 m/s
Position (m)
5.0
The velocity is 0.67 m/s to the west
4.0, 0.0
p. 104 # Do
Time (s)
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82. Vector Meaning of +/- d where you are at v where you are going
a ambiguous
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83. Non-Uniform (acceleration) Motion Graphs

84. Displacement – Time Graphs for Non Uniform Motion (acceleration)
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85. Curved segments on the D-T graph mean the object’s speed is changing.
time (s)
pos. (m)
Speeding up in positive direction.
time (s)
pos. (m)
Speeding up in negative direction.
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86. Curved segments on the P-T graph mean the object’s speed is changing.
time (s)
pos. (m)
Traveling in positive direction, but slowing down.
time (s)
pos. (m)
Traveling in negative direction, but slowing down.
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87. Displacement – Time Graphs (Non-uniform Motion)
Compare:
Constant speed (Uniform Motion)
time
displacement
Accelerating (Non-uniform Motion)
time
displacement
This graph gradually gets steeper
The steeper the line the faster the speed.
p. 111 # Do
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88. The following P-T graph corresponds to an object moving back and forth along a straight path. Can you describe its movement based on the graph?
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89. time (s)
position (m) N S

90. Velocity – Time Graphs for Non Uniform Motion (acceleration)
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91. Page 111
Velocity – Time Graphs (Non-uniform Motion)
Constant velocity
time
velocity
Accelerating (non-uniform motion)
time
velocity
The steeper the line the greater the acceleration.
The acceleration of an object can be determined using the slope of a velocity-time graph.
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92. Graph a is steeper (larger slope) therefore greater acceleration.
Example
time
velocity
Identify the graph representing motion having the greater acceleration. a. b.
Graph a is steeper (larger slope) therefore greater acceleration.
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93. The area between the graph and x-axis = displacement
Velocity – Time Graphs
time
velocity
The area between the graph and x-axis = displacement
Slope = acceleration
Area = displacement
p. 112 # Do
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94. Slope/Area Relationshipd v a
area
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95. Strategy – examine one column at a time
Example
A speed-time graph for a car is shown below. The slope of the graph is the _____i____ and the area is the ___ii_____
v(m/s)
t (s) i ii a.
acceleration
velocity b.
distance c. d.
Strategy – examine one column at a time
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96. Transposing Graphs
Transposing graphs is changing one type of graph to another type of graph both representing the same motion.
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97. Line trends Acceleration Constant velocity Stationary d v curve
diagonal
horizontal
zero d v
Acceleration
Constant
velocity
Stationary
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98. Line Trends d v a d v a d v a d v slope area zero horizontal curve
diagonal d v a d v a d v
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99. Motion Motion may communicated using words, equations or graphs.
We must be able to translate between the three different modes of communications.
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100. Transposing graphs – remember the trends
Graphing Summary d v a
slope
area
Transposing graphs – remember the trends
zero
horizontal
curve
diagonal d v a d v a d v
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101. Examine and compare one section at a time
zero
horizontal
curve
diagonal d v a d v a d v
Example d t
Examine and compare one section at a time
Identify the v- t graph that best corresponds with the d-t graph a. b. c. d. e.
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102. Examine and compare one section at a time
zero
horizontal
curve
diagonal d v a d v a
Example v t
Examine and compare one section at a time
Identify the d- t graph that best corresponds with the v-t graph a. b. c. d. e.
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103. Graph Summary d v a d v a d v a d v slope area zero horizontal curve
diagonal d v a d v a d v
p. 113 #23, 24 Do
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