Dr. Tatiana Erukhimova
[year]
Overview of Today’s Class
•Folders
•Syllabus and Course requirements
•Tricks to survive
•Mechanics Review and Coulomb’s Law
Please take the folders
Section 807 (recitation starts at 8:00 am R) – red folders
Section 808 (recitation starts at 2:20 pm R) – yellow folders
Section 809 (recitation starts at 4:55 pm R) – green folders
Section 523 (recitation starts at 11:10 am R) – blue folders
If you forgot your Section number,
please check it with me
We’ll use the folders only in class:
Please pick them up before each class and return
back after the class
DO NOT take them home!
I’ll return the quizzes in these folders
Syllabus
Instructor Dr. Tatiana Erukhimova
Homepage http://faculty.physics.tamu.edu/etanya/P208/
Office: Mitchell Physics bldg (MPHY), Room 308
Phone: 845-5644
E-mail: etanya@tamu.edu
Class times: MWF: 9:10 am to 10:00 am
Sections 807-809, 523
Location: MPHY 205
Office hours:
Monday and Wednesday 1pm – 3pm or
by appointment
Textbook: “Don’t Panic: Volume II”, by
William H. Bassichis, 5th Edition
Dedicated
students like it!
No lab manual is required
Grade Policy
Exams 45%
Lab 5%
Quizzes 10%
Final 40%
Grade Policy (cont)
You must pass both the lecture
(3 midterm exams, final exam, homework)
and laboratory parts of the course
in order to pass the course
Grade Policy (cont)
•If your grade on the Final Exam is higher
than your lowest grade on one of the three
exams during the semester, the grade on the
Final will replace that one lowest exam grade
in computing the course grade (it will only
replace one grade in case of two exams having
the same lowest grade).
•The Final Exam grade cannot be used to
replace an exam that has been missed without
an University excused absence. The missed
exam will count as a zero when computing
your final grade.
All Exams are
•Closed book
•No numbers! In general the problems will be
formula solutions with variables
•Problems will be similar to those on
homework and recitation
Homework
You’ll have weekly homework assignments
Every week you’ll have hw quiz (for 10 min)
with one problem from your assignment.
Good news: you are allowed to use YOUR notes
(no books or photocopies)
Bad news: small partial credit (for hw). You
have to show your work, get a correct formula,
and, if required, a numerical answer
Check my webpage for hw assignments
Example for Week 1 (Week Jan 17):
Week Jan 17 (due Jan 24): All Chapter 1
problems and exercises
“Due” means that I’ll give you a hw quiz on
that day
Homework (Cont)
Reading quizzes
Please buy clickers (CPSrf responder)
You will need to buy the clickers at the MSC Bookstore
and register them for this class at http://elearning.tamu.edu
(NOT www.einstruction.com)
You will earn points for reading quizzes based on your
participation in class as documented via use of your CPSrf
responder. You will not be able to earn points if you fail to
bring your personally registered CPSrf responder with you
to class each day.
Exam schedule
All mid-term exams will be from 7:00 to 9:30 pm?
February 15
March 22
April 20
Final
Exam I
Exam II
Exam III
May 9
My Advise to You
• Be proactive!! Get into it and have fun
• Always read the book before you come to class
• Be serious about an old rule of thumb: you have to
study 2-3 hours a week outside the class per each
credit hour
• Don’t miss classes (lectures, recitations, labs)
• Solve all problems and exercises after each Chapter
in the book
• Don’t fall into the “I understand the concepts but I
can’t do the problems” trap. It means you haven’t
done enough of the problems in the chapters.
• Every year we have lots of students who really think
they understand but fail during the exams. Don’t let
this happen to you!
Help sessions are every Monday 15 min
before the class
I also make help sessions before each
midterm exam and the final. (and Monday?)
However,
these
sessions
cannot
substitute for regular class attendance. They
are to give you a good guidance on how to
prepare for the test and to succeed in problem
solving.
Please check my webpage for help sessions
schedule
Richard P. Feynman
1918-1988
Nobel Prize in Physics, 1965
From long view of the history of mankind – seen from, say,
ten thousand years from now – there can be little doubt
that the most significant event of the 19th century will be
judged as Maxwell’s discovery of the laws of electrodynamics.
The American Civil War will pale into provincial insignificance
in comparison with this important scientific event of the same
decade.
A little bit of Mechanics
A couple of very important concepts:
r
r2
2
2
r
r mV final mVinitial
W   F____

total dr 
r
2
2
r1
W
x2 y 2
x2 y 2
x1 y1
x1 y1
total
F
 x dx 
W W
total
F
 y dy 
conservative
W
mV
2
final
2
non conservative
2
mVinitial

2
W
W
conservative
conservative
does NOT depend on path!


 [U (r2 )  U (r1 )]
U
U
Fx  
; Fy  
x
y
W  W conservative  W nonconservative 
2
2


mV
mV
2
1
 [U (r2 )  U (r1 )]  W nonconservative 

2
2
W
non conservative
2
2


mV2
mV1
 U (r2 ) 
 U (r1 ) 
2
2
W
non conservative
If
W
2
2
2
1

 mV
mV
 U (r2 ) 
 U (r1 ) 
2
2
non conservative
 0,
2
2
2
1

 mV
mV
U (r2 ) 
 U (r1 ) 
2
2
Mechanical energy is conserved!
We can find Gravitational Potential Energy
U (r ,  )
U (r ,  )
Fr  
; F  
r
r

m1m2 
Fg  G 2 ir
r
m1m2
m1m2
U (r )     G 2 dr  G
 Const
r
r
U ()  Const  0
m1m2
U (r )  G
r

i

Fr

ir
Consider now a different type of a force…..
Consider a force like gravitation which varies as
1
r2
but 1) billion-billion-billion-billion times stronger;
2) there are two kinds of “matter”: positive and
negative; Like kinds repel and unlike kinds
attract (unlike gravity where there is only
attraction)
+
+
+
_
_
_
Electrical force
All matter is a mixture of positive protons and negative electrons which
are attracting and repelling with this great force.
How perfect is the balance?
-when you stand near someone else you don’t feel any force at all;
-if you were standing at arm’s length from someone and each of you had
one percent more electrons than protons, the repelling force would be
enough to lift a “weight” equal to that of the entire earth!
The force that holds atom together, and the chemical forces
that holds molecules together, are electrical forces!
Have a great day!
Hw: All Chapter 1 problems
and exercises
Reading: Chapter 1