1. Professor Fatma Salman <fsalman@atlas.valenciacc.edu>
Welcome to 1053
9/19/2018
2048 Ch. 1-2

2. Class Meets Tuesday, Thursday 6:30-9:20 PM
9/19/2018
2048 Ch. 1-2

3. Textbook Physics Volume I (Mechanics) Cutnell & Johnson 7th Edition
9/19/2018
2048 Ch. 1-2

4. Grades Item Weight Mid Semester Examinations 40 % Final Examination
30%
Homework
15%
Labs
9/19/2018
2048 Ch. 1-2

5. Homework
It is important to notice that homework counts for 15% of your grade. Although “extensions” will be available, valid reasons should be offered at the time she or he request.
There will be one assignment per chapter. Each assignment will contain between 5 and 12 problems (usually). You must complete the assignment before the due time or you must request an extension. You will need a reason.
9/19/2018
2048 Ch. 1-2

6. No Curve SCORE GRADE 90-100 A 80-89 B 70-79 C 60-69 D Less than 60 F
9/19/2018
2048 Ch. 1-2

7. Approximate Exam Schedule
EXAM NUMBER
DATE 1
6/1/07 2
6/27/07
FINAL EXAM
8/1/07
9/19/2018
2048 Ch. 1-2

8. My gripes …. Students study at the last minute.
Students have big holes in their math skills:
Interpreting Graphs.
Using Calculus.
Students come to my office expecting me to solve their homework problems.
I will always help … I will not give you the answers!
Work on the problems before you come for help.
9/19/2018
2048 Ch. 1-2

9. How to get an A.
STUDY !
9/19/2018
2048 Ch. 1-2

10. PHY1053 Mechanics The physics of how classical objects move. Terms
mass, distance, time
Force, torque
displacement, speed, acceleration
momentum, energy
angular analogs
Issues for many students
calculus, graphical interpretation
9/19/2018
2048 Ch. 1-2

11. Systems of Units SI Units …. Meters, Seconds, Newton, Kilograms
English System ….. Feet/yards, seconds, pounds
9/19/2018
2048 Ch. 1-2

12. The real standard:
The Meter
9/19/2018
2048 Ch. 1-2

13. More Important Definitions
TIME
The subjective “distance” between two EVENTS.
It needs to be objective … ie measurable and reproducible.
Today’s Clocks –
“He ran the race in 4 hours, 2 minutes and seconds”
9/19/2018
2048 Ch. 1-2

14. Sun Clock
9/19/2018
2048 Ch. 1-2

15. Water Clocks
9/19/2018
2048 Ch. 1-2

16. Pendulum Clocks We will study how a pendulum works
later in the semester.
9/19/2018
2048 Ch. 1-2

17. Cuckoo Clock Cuckoo’s are not covered in this class. 9/19/2018
2048 Ch. 1-2

18. And so on … Rolex (~$10K) Atomic Clock (NASA) $ megabucks 9/19/2018
2048 Ch. 1-2

19. Mass The Standard Kilogram
A “quantity of matter”.
Locked up in Paris.
We have copy
9/19/2018
2048 Ch. 1-2

20. Prefixes
9/19/2018
2048 Ch. 1-2

21. Unit Conversion- How many seconds old are you?
Assume you are exactly 21 years old
9/19/2018
2048 Ch. 1-2

22. So …
=21 x 365 x 24 x 60 x 60 sec = 662,256,000 sec
= 6.62 x 108 seconds
9/19/2018
2048 Ch. 1-2

23. Example
9/19/2018
2048 Ch. 1-2

24. The Consequences of Vectors
You need to recall your trigonometry if you have forgotten it.
We will be using sine, cosine, tangent, etc. things.
You therefore will need calculators for all quizzes from this point on.
9/19/2018
2048 Ch. 1-2

25. Hey … I’m lost. How do I get to lake Eola
NO PROBLEM!
Just drive 1000 meters and you will be there. B
HEY!
Where the am I?? A
9/19/2018
2048 Ch. 1-2

26. The moron drove in the wrong direction!
The problem:
The moron drove in the wrong direction!
9/19/2018
2048 Ch. 1-2

27. IS this the way (with direecton now!) to Lake Eola?B
THIS IS A VECTOR A
9/19/2018
2048 Ch. 1-2

28. Vectors and Scalars
A scalar quantity is completely specified by a single value with an appropriate unit and has no direction.
A vector quantity is completely described by a number and appropriate units plus a direction.
9/19/2018
2048 Ch. 1-2

29. Vector Notation When handwritten, use an arrow:
When printed, will be in bold print: A
When dealing with just the magnitude of a vector in print, an italic letter will be used: A or |A|
The magnitude of the vector has physical units
The magnitude of a vector is always a positive number
9/19/2018
2048 Ch. 1-2

30. Vector Example
A particle travels from A to B along the path shown by the dotted red line
This is the distance traveled and is a scalar
The displacement is the solid line from A to B
The displacement is independent of the path taken between the two points
Displacement is a vector
9/19/2018
2048 Ch. 1-2

31. Equality of Two Vectors
Two vectors are equal if they have the same magnitude and the same direction
A = B if A = B and they point along parallel lines
All of the vectors shown are equal
9/19/2018
2048 Ch. 1-2

32. Coordinate Systems Used to describe the position of a point in space
Coordinate system consists of
a fixed reference point called the origin
specific axes with scales and labels
instructions on how to label a point relative to the origin and the axes
9/19/2018
2048 Ch. 1-2

33. Cartesian Coordinate System
Also called rectangular coordinate system
x- and y- axes intersect at the origin
Points are labeled (x,y)
9/19/2018
2048 Ch. 1-2

34. Polar Coordinate System
Origin and reference line are noted
Point is distance r from the origin in the direction of angle , ccw from reference line
Points are labeled (r,)
9/19/2018
2048 Ch. 1-2

35. Polar to Cartesian Coordinates
Based on forming a right triangle from r and q
x = r cos q
y = r sin q
9/19/2018
2048 Ch. 1-2

36. Cartesian to Polar Coordinates
r is the hypotenuse and q an angle
q must be ccw from positive x axis for these equations to be valid
9/19/2018
2048 Ch. 1-2

37. Example
The Cartesian coordinates of a point in the xy plane are (x,y) = (-3.50, -2.50) m, as shown in the figure. Find the polar coordinates of this point.
Solution: From Equation 3.4,
and from Equation 3.3,
9/19/2018
2048 Ch. 1-2

38. If the rectangular coordinates of a point are given by (2, y) and its polar coordinates are (r, 30), determine y and r.
9/19/2018
2048 Ch. 1-2

39. Adding Vectors Graphically
9/19/2018
2048 Ch. 1-2

40. Adding Vectors Graphically
9/19/2018
2048 Ch. 1-2

41. Adding Vectors, Rules
When two vectors are added, the sum is independent of the order of the addition.
This is the commutative law of addition
A + B = B + A
9/19/2018
2048 Ch. 1-2

42. Adding Vectors
When adding three or more vectors, their sum is independent of the way in which the individual vectors are grouped
This is called the Associative Property of Addition
(A + B) + C = A + (B + C)
9/19/2018
2048 Ch. 1-2

43. Subtracting Vectors Special case of vector addition
If A – B, then use A+(-B)
Continue with standard vector addition procedure
9/19/2018
2048 Ch. 1-2

44. Each of the displacement vectors A and B has a magnitude of 3. 00 m
Each of the displacement vectors A and B has a magnitude of 3.00 m. Find graphically (a) A + B, (b) A  B, (c) B  A, (d) A  2B. Report all angles counterclockwise from the positive x axis.
9/19/2018
2048 Ch. 1-2

45. Components of a Vector A component is a part
It is useful to use rectangular components
These are the projections of the vector along the x- and y-axes
9/19/2018
2048 Ch. 1-2

46. Unit Vectors, cont. The symbols represent unit vectors
They form a set of mutually perpendicular vectors
9/19/2018
2048 Ch. 1-2

47. Unit Vectors in Vector Notation
Ax is the same as Ax and Ay is the same as Ay etc.
The complete vector can be expressed as
9/19/2018
2048 Ch. 1-2

48. Adding Vectors with Unit Vectors
9/19/2018
2048 Ch. 1-2

49. Adding Vectors Using Unit Vectors – Three Directions
Using R = A + B
Rx = Ax + Bx , Ry = Ay + By and Rz = Az + Bz
9/19/2018
2048 Ch. 1-2