4. Students are expected to:
Use instruments and terminologies effectively and accurately for collecting data in various experiments.
Describe the relationship among distance, time, and average speed of an object’s linear motion.
Describe examples of Canadian contributions to science and technology in the area of motion

5. 9.1 – Getting Into Motion Physics is the study of motion.
What do you think motion is? Write down 5 things that relate to motion.

6. What is MOTION

7. What is motion?
When a body is continuously changing its position with respect to the surroundings, then we say that the body is in motion.

8. Motion
Motion is a change in position relative to a frame of reference.

9. Examples:
1. When an athlete is running on the ground then he is continuously changing his position with respect to the audience who are sitting at rest.
2. We are continuously changing our position since morning till night with respect to earth which is at rest.
3. The earth is continuously changing position with respect to sun which is at rest.

12. Remember: Motion is: The act or process of changing position or place.
The ability or power to move.
The manner in which the body moves.

13. Question!
When two different objects are dropped at the same height, which object lands first?

14. When thinking about physics and motion there are two key concepts to remember:
1. Heavy objects and light objects, if dropped from the same height, fall to Earth in the same amount of time.
2. An object rolled down an incline will return to its original height, if the incline curves back up again. If the incline levels out instead, the object will continue rolling.

15. 9.2 – The Language of Motion
Every term in physics has:
A single, precise meaning.
A standard set of symbols
A particular SI unit of measurement.

16. Measurements are always approximate.
Precision
Measurements are always approximate.
They depend on the precision of the measuring instruments that were used.
E.g. On a metric ruler, you can measure to mm as the smallest unit; if you measure 1.5mm you are estimating the last digit.

17. Significant Figures
Scientists agree that calculated answers should be rounded so that they do not give a misleading idea of how precise the original measurements were.
E.g = 4.24
When we round this answer to the correct number of significant figures, we get 4.2!!

18. Motion is measured in quantities: LINEAR MOTION
In many experiments objects move in a straight line in only one dimension: backward/forward or up/down. This is called linear motion.
Motion is measured in quantities:
LINEAR MOTION
SCALAR QUANTITY has a magnitude (size) but no direction.
VECTOR QUANTITY states the magnitude (size) and direction.

19. MOTION FORMULA
v – velocity
d – distance
t – time

20. DISTANCE
DISTANCE - measures the total length of a journey along every twist and turn of the path/way. Distance is a scalar quantity.
SCALAR QUANTITY has a magnitude (size) but no direction.
Symbols:
d - distance
di - initial distance
df - final distance
∆d - distance interval or also called as change in distance
(also read as ‘delta d” , delta means change)
Calculation: ∆d = df – di
Standard Unit : metre (m)
Example:
The race covered a distance of 5.62 km along the winding banks of the river.

21. Measuring Distance Meter – international unit for measuring distance.
1 mm
= 50 m

22. TIME
TIME – describes when an event occurs. TIME INTERVAL describes the duration of an event. Time is a scalar quantity.
Symbols:
t - time
ti - initial time
tf- final time
∆t - time interval
Calculation: ∆t = tf – ti
Standard Unit: second (s)
Example:
About 30 min into the movie (time), Amy went out of the theatre for about 5 min (time interval).

23. POSITION
POSITION –describes an object’s location, as seen by an observer from a particular viewpoint. Position is a vector quantity.
VECTOR QUANTITY states the magnitude (size) and direction.
Symbols:
(The arrow over the letter ‘d” means “vector”.)
Standard Unit: metre (m)
Example:
The collision occurred m due south of the flagpole.
(Positions : south, north, west, east, upward, downward, to the left, to the right, different angles)

24. DISPLACEMENT
DISPLACEMENT – describes how much an object’s position has changed. Displacement is a vector.
Symbol:
Calculation:
Standard Unit: metre (m)
Example:
We pushed the car, producing a displacement of 4.5 m at an angle of 250 to the road.

25. Activity
Answer the exercise hand out.

26. SPEED
SPEED – describes how fast something is moving. Speed is a scalar.
Symbol:
v or |v|
Standard unit: metre per second (m/s)
Example:
The cyclist reached a maximum speed of m/s during the race.

27. Calculating Speed V = d/t
Speed (v) = distance traveled (d) / the amount of time it took (t).
V = d/t

28. How do we calculate speed?
Speed – the distance the object travels in one unit of time
Speed = distance
time

29. Calculating speed v = d/t
If I travel 100 kilometer in one hour then I have a speed of…
100 km/h
If I travel 1 meter in 1 second then I have a speed of….
1 m/s

30. What is constant speed?
If the speed of an object does not change, the object is traveling at a constant speed .

31. What is average speed?
Most objects do not travel at constant speed
To find average speed divide the total distance by the total time
Average Speed = distance 2-distance 1
time 2-time 1

32. Average Speed Speed is usually NOT CONSTANT
Ex. Cars stop and go regularly
Runners go slower uphill than downhill
Average speed = total distance traveled/total time it took.

33. Calculating Average Speed
It took me 1 hour to go 40 km on the highway. Then it took me 2 more hours to go 20 km using the streets.
Total Distance:
40 km + 20 km = 60 km
Total Time:
1 h + 2 h = 3 hr
Ave. Speed:
total d/total t = 60 km/3 h = 20 km/h

34. Question
I travelled 25 km in 10 minutes. How many meters have I travelled?
A) m
B) m
C) .025 m
D) 2.5 m
25 km * 1000m/km = m

35. What is Velocity? - Speed in a given direction.
When you know the speed and direction of an object’s motion, you know the velocity of the object
Example:
15 km/hour westward

36. Velocity or Not?
25 m/s forward
1500 km/h
55 m/h
93 m/s south
Yes No

37. Question
I ran 1000 m in 3 minutes. Then ran another 1000 m uphill in 7 minutes. What is my average speed?
A) 100 m/min
B) 2000 m/min
C) 10 m/min
D) 200 m/min
E) 20 m/min
Total Dist. = 1000 m m = 2000 m
Total Time = 3 min + 7 min = 10 min
Ave speed = total dist/total time =
2000m/10 min = 200 m/min = D

38. VELOCITY
VELOCITY – describes the speed and direction of motion. It describes how fast an object’s position is changing. Velocity is a vector.
Instantaneous Velocity - velocity at a specific instant in time.
Average Velocity – the average velocity over a particular time interval.
 Symbols:
Calculation:
Standard Unit: metre per second (m/s)
Example:
The aircraft was travelling at 535 km/h, headed N450W, when the weather warning was received.

39. Velocity Velocity – the SPEED and DIRECTION of an object. Example:
An airplane moving North at 500 mph
A missile moving towards you at 200 m/s

40. Question What is the difference between speed and velocity?
Speed is just distance/time. Velocity includes direction as well.
Speed is just distance/time. Velocity includes direction as well.

41. The rate at which velocity changes In science, acceleration refers to:
What is Acceleration?
The rate at which velocity changes
In science, acceleration refers to:
increasing speed
decreasing speed
changing direction

42. How do you calculate acceleration?
To determine the acceleration rate of an object, you must calculate the change in velocity during each unit of time
Acceleration = Final velocity – Initial velocity
Time

43. ACCELERATION
ACCELERATION – describes how much an object’s velocity changes in a certain time. Acceleration is a vector.
Symbols:
– average acceleration
– instantaneous acceleration

45. Acceleration Acceleration = speeding up
Acceleration – the rate at which velocity changes
Can be an:
Increase in speed
Decrease in speed
Change in direction

46. Types of Acceleration Increasing speed Decreasing speed
Example: Car speeds up at green light.
Decreasing speed
Example: Car slows down at stop light.
Changing Direction
Example: Car takes turn (can be at constant speed).
screeeeech

47. For displacement and velocity:
A+ indicates up or toward the observer’s right
A- indicates down or toward the observer’s left

48. Calculating Acceleration
0 s
1 s
2 s
3 s
4 s
0 m/s
4 m/s
8 m/s
12 m/s
16 m/s

49. Question
A skydiver accelerates from 20 m/s to 40 m/s in 2 seconds. What is the skydiver’s average acceleration?

50. Homework
Quiz Next Meeting!

51. 9.3 Measuring Motion Basic tools for studying motion:
A watch – for measuring time
Metre stick – for measuring the length or distance
Calculator – for calculating, especially big numbers

52. MEASURING MOTION Other measuring instruments:
1) Metronomes and markers – use to track motion of an object
2) Ticker timers – use to measure speed of an object ( motion device)
3) Ultrasonic motion sensors – use to calculate the distance of an object by means of a sensor and a computer
4) Photogate timers – use to detect changes in light intensity as it shaded by a passing moving object

53. For position:
A+ indicates up or to the right of the starting point
A- indicates down or to the left of the starting point

54. For displacement and velocity:
A+ indicates up or toward the observer’s right
A- indicates down or toward the observer’s left

55. Rate of Change
The symbol ∆ is used to indicate a change in a quantity. To determine the change of position or time, it is always calculated by subtracting the initial state from the final state. In Mathematics, a RATE describes how a quantity is changing.
In Physics, the term RATE OF CHANGE means how fast a quantity is changing over time. Velocity is the rate of change in position ( v = /t) while acceleration is the rate of change in velocity ( a = v/t).

56. Average Rate of Change = total change / time interval = final state – initial state / final time- initial time
Rate of Change in Velocity
Rate of Change in Position

57. Steps on problem solving (in Physics):
1) Read the situation at least twice carefully and identify the problem.
2) Draw a sketch to represent the problem.
3) Write down the given information.
4) State what is required in the problem.
5) Analyze and decide what formula to use in solving the problem.
6) Substitute the given information to the formula and show your solution.
7) Double-check the answer of the problem.
8) Always state the answer in sentence form using a complete standard of unit asked in the problem.
(Refer on page 311 for sample problems of the rate of change.)

58. Using Graphs
Graphs are used to illustrate or exhibit the relationship of two quantities or set of points. It is a powerful tool for analyzing numerical data. A graph was discovered by RENE DESCARTES, a French mathematician. Here are three reasons why it is very useful:
Patterns in data can be often identified more clearly in graphs than using a table.
Graphs can correct errors/mistakes in the observations.
Calculating useful information is often simpler using a graph.

59. How do you interpret motion graphs?
A straight line indicates a constant speed
The steepness depends on how quickly or slowly the object is moving
The faster the motion the steeper the slope.

60. Graphing Speed Distance vs. Time Graphs
Denver
Phoenix

61. Graphing Speed Distance vs. Time Graphs
Speed = Slope = Rise/Run
Rise

62. Graphing Speed Distance vs. Time Graphs
Speed = Slope = Rise/Run
Rise=?
600 km
3 h

63. Graphing Speed: Distance vs. Time Graphs
Speed = Slope = Rise/Run
Rise=?
600 m
3 minutes
Rise/Run = 600 km/3 hr
= 200 km/hr

64. Different Slopes Slope = Rise/Run = 0 km/1 hr = 0 km/hr Rise = 2 km
Run = 1 hr
Rise = 0 km
Run = 1 hr
Slope = Rise/Run
= 2 km/1 hr
= 2 km/hr
Rise = 1 km
Run = 1 hr
Slope = Rise/Run
= 1 km/1 hr
= 1 km/hr

65. Average Speed = Total distance/Total time = 12 km/6 hr
Question
Below is a distance vs. time graph of my position during a race. What was my AVERAGE speed for the entire race?
Average Speed = Total distance/Total time = 12 km/6 hr
= 2 km/hr
Rise = 12 km
Run = 6 hr

66. Question
What does the slope of a distance vs. time graph show you about the motion of an object?
It tells you the SPEED.

67. Question
Below is a distance vs. time graph for 3 runners. Who is the fastest?
Leroy is the fastest. He completed the race in 3 hours.

68. Graphing Acceleration
Can use two kinds of graphs:
Speed vs. Time
Distance vs. Time

69. Graphing Acceleration: Speed vs. Time Graphs
Speed is increasing with time = accelerating
Line is straight = acceleration is constant

70. Graphing Acceleration: Speed vs. Time Graphs
Rise = 4 m/s
Run = 2 s
In Speed vs. Time graphs:
Acceleration = Rise/Run
= 4 m/s ÷ 2 s = 2 m/s2

71. Graphing Acceleration: Distance vs. Time Graphs
On Distance vs. Time graphs a curved line means the object is accelerating.
Curved line also means your speed is increasing. Remember slope = speed.

72. Question Run = 3 s Rise = -6 m/s The car is slowing down
Above is a graph showing the speed of a car over time.
1) How is the speed of the car changing (speeding up,
Slowing down, or staying the same)?
2) What is this car’s acceleration?
The car is slowing down
Acceleration = rise/run = -6m/s ÷3s = -2 m/s2

73. curved line = accelerating, flat line = constant speed
Question:
The black and red lines represent a objects that are accelerating. Black is going a greater distance each second, so it must be speeding up. Red is going less each second, so must be slowing down
Remember: in distance vs. time graphs:
curved line = accelerating, flat line = constant speed
Which line represents an object that is accelerating?

74. Activity
Please answer the exercise hand out within class time and submit your work when the class is over.

75. Homework
HOMEWORK:
Answer questions # 1, 2 , 4, 6 and 7 on pages
WEEKEND HOMEWORK
Copy and answer Chapter Review # 1-8, 10 and 12.

76. Activity Note: Turn to page 302-303 of your textbook.
Perform WHAT TO DO
Complete the table in the handout.
Answer : (at the bottom)
From your experience with compass directions and RCS descriptions which system do you prefer? Why?
Note:
RCS – Rectangular Co-ordinate System
Refer to page 303.