1. Physical Science Chapter 11 Motion Chapter pg.328
11.1 Distance and Displacement
11.2 Speed and Velocity
11.3 Acceleration
Richard E. Clemons M.S.
MNHHS
MARCH., 2008

2. Motion Are we in this room in Motion? Y or N
Both answers are correct due to the following reasons;
A) no because our position to the floor, walls, and ceiling is not changing
B) yes, as a part of the earth we are rotating and revolving constantly

3. 11.1 pg.328 Distance & Displacement
All forms of motion has to be judged by an outside factor
The concept is based on a frame of reference or a reference object
These reference items are best chosen as items that under NORMAL conditions can not move

4. Reference
A reference object is any object that we can use to define determine if a change in an objects position has occurred
Any object that can move under normal conditions is NOT the best choice to use for determining motion
Best items; those that normally Stationary usually the ones that are attached to the Earths surface
Examples; trees buildings road signs

5. Relative motion
All motion is relative until proof of that movement can be presented
That is a change in the objects position as compared to a reference item attached to the earth
This motion can then be measured for distance moved and the time it took that distance to be covered

6. Distance
Is the measured value that connects two points when in a straight line the calculation is simple
A line is shortest distance between two points
Standard unit for length (dist) in science is the METER and we add prefixes for longer or shorter values

7. SI / Metric system for distance
Base unit METER
Prefixes
Larger value
Giga = billion
Mega = million
Kilo = thousand
Smaller value
Deci = 1/10
Centi = 1/100
Milli = 1/1000

8. Quantity
Information that is obtained and provides us with specific data places for analysis
This data provided falls into two categories
A) Scalar quantity
B) Vector quantity

9. Scalar Quantity
A description of an item that is focused on One factor only
The focus is on MAGNITUDE
Magnitude is a measurement value, thus it must have a number an label
Single dimension (definite quantity)
Time, temperature, length, mass, direction

10. Vector Quantity
A description of an item that contains TWO components of information
Like a scalar quantity it also contains a magnitude value
Unlike a scalar quantity a vector also includes a second component, direction
Vectors are then Magnitude with Direction

11. Displacement This item is a two part factor for motion A) distance
B) direction
When both distance and direction are combined it can provide a large amount of information
5Km or 5Km to the East
Which one is best for providing a direction to a stranger to your area?

12. Resultant vector
The resultant vector is the vector that is produced that equals the sum of the vectors involved in the problem
That is, gets you from the starting point to the ending point in the shortest distance or the new velocity and direction caused by the interaction of multiple vectors on an object

13. Resultant vector
There are four methods that we will focus on for solving multiple vectors of interaction
A) adding
B) subtracting
C) Pythagorean theorem a2 + b2 = c2 written as r2 = a2 + b2
D) law of cosines r2 = a2 + b2 – 2abcos(theta)

14. Solving vectors Adding Subtract
Combine the two values by adding if and only if the parts are going in the same direction
Subtract
Combine the two values by subtracting if and only if the parts are going in the opposite direction

15. Solving vectors Pythagorean theorem Law of Cosines
If the two parts form a right angle and the finishing side completes a right triangle
Law of Cosines
Use for any vector that does not fit the other styles and when the final side is added you have created a triangle that is acute and/or obtuse (any style other than a right triangle)

16. Distance: Displacements Along a Line
Figure 3
Distance: Displacements Along a Line

17. Distance: Displacements Along a Line
Figure 3
Distance: Displacements Along a Line

18. Distance: Displacements Along a Line
Figure 3
Distance: Displacements Along a Line

19. Distance: Displacements Along a Line
Figure 3
Distance: Displacements Along a Line

20. Distance: Displacements Along a Line
Figure 3
Distance: Displacements Along a Line

21. Speed or Velocity sect 11.2 pg 332
The math portion is the same equation
Rate = distance / time
That is how fast is equal to total distance divided by total time
Since direction will be necessary at some time the term velocity is a better choice So
VELOCITY (V) = DISTANCE (D) / TIME (T)

22. Calculating Average Speed
Section 11.2
Calculating Average Speed

23. Calculating Average Speed
Section 11.2
Calculating Average Speed

24. Calculating Average Speed
Section 11.2
Calculating Average Speed

25. SLOPE pg 334
On a graph the velocity or rate of motion can be found by finding the slope of a line
Slope = rise / run
Slope = change in Y’s/change in X’s

26. Distance-Time Graphs for Motion of Three Cars
Section 11.2
Distance-Time Graphs for Motion of Three Cars

27. Acceleration sect 11.3 pg 342
Acceleration is the rate at which velocity changes against time
How fast the rate is increased or decreased or the direction changes
Acceleration equals final velocity minus starting velocity divided by time
A = VF – VI / t

28. Acceleration
Summary
Any change in the following can technically be a form of acceleration
Faster velocity
Slower velocity
Change to direction

29. Acceleration
Name three items in / on a car that can control acceleration
Gas pedal
(accelerator)
Brake pedal
(decelerator)
Steering wheel
(change direction)

30. Measuring Acceleration
Section 11.3
Measuring Acceleration

31. Measuring Acceleration
Section 11.3
Measuring Acceleration

32. Measuring Acceleration
Section 11.3
Measuring Acceleration

33. acceleration graphs pg 346
Figures 16 and 17
acceleration graphs pg 346

34. Distance-Time Graph of Accelerated Motion
Figure 18
Distance-Time Graph of Accelerated Motion

35. Average or Constant or Instantaneous
Average is the comparison of TOTALS; total distance / total time
Constant (uniform) NO change in the rate or direction
Instantaneous what is happening at a specific moment (how fast when you look at the speedometer of the car)

36. Equations Velocity *V=d/t *d=v*t *t=d/v Vectors
*Add (same) *subtract (opposite) *Pythagorean c2= a2 + b2

37. Equations Slope *Slope = rise/run *slope = y2 – y1 / x2 – x1
Acceleration
*a = VF – VI / t *t = VF – VI /a *v (change) =a*t