Welcome to Physics I !!!

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Welcome to Physics I !!!
LECTURE 1

• Prof. Wasserman

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(No Transcript)
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Outline

• Why Physics?
• Course organization
• Course grading
• Chapter 1
• Significant figures
• Units
• Estimating

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Why Physics?

• Students in this course come from diverse
  backgrounds and are heading in diverse directions
• Physics provides all with a scientific toolbox
• Physics describes the fundamental operation of
  the world around us Engineering, Chemistry,
  Biology, Astronomy, etc.
• Teaches us how to approach complex problems
• Science is inherently progressive
• If approached correctly, we can all contribute!
• What you are going to do matters!

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Physicists look at the world differently

• This class will attempt to show you how we
  understand the world around us

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Course Organization

• Everything you need to know about the course can
  be found on the course website
  http//faculty.uml.edu/dwasserman/95.141.htm

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Course Communication

• Website
• http//faculty.uml.edu/dwasserman/95.141.htm
• Physics I Twitter account _at_UMLPhysicsIS10
• On Facebook, search for "UML Physics I S2010"

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Course Organization

• Physics I meets 4 times a week
• Lectures
• 230-320 MW, OH 150
• Recitation Sections
• Varying times, locations
• Know your instructor and section number!!!
• Homework review sessions
• 630-930 pm, OH 218
• Held every week before HW is due
• Textbook Giancoli Physics for Scientists and
  Engineers, 4th Ed.
• NO LAB THIS WEEK!!
• RECITATION SECTIONS THIS WEEK!!

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Lecture Organization

• Exam Prep. Problem
• Review of Previous Lecture
• Lecture Main Topic
• Will include clicker questions
• Example problems
• Symbolic
• Numerical
• Movie clips
• Demonstrations
• Summary
• LECTURES MOVE FAST!!!

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Lectures

• NO COMPUTERS IN LECTURE!!
• NO CELL PHONES!!
• NO TALKING!!

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Recitation Section Organization

• Lecture Summary
• Example problems from Book
• Quizzes

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Course Grading

Item Points
Standard HW 90
LP HW 20
Quizzes 90
Participation 30
Exam 0 20
Exam 1 100
Exam 2 100
Exam 3 100
Final Exam 200
Total 750
Range Grade
gt600 A
560-599 B/A-
490-559 B
450-489 C/B-
375-449 C
340-374 D/C-
265-340 D
lt265 F
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PRS Clickers

• For detailed info on setting up PRS clickers, go
  to http//clickers.wiki.uml.edu/StudentResources
  
• You must have your own clicker!!
• You cannot borrow a friends clicker for class
• You may not have more than 1 clicker in class
  this is academic fraud.
• Clickers will be used to determine part of
  participation grade

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Lets Set-Up Our PRS Clickers

• Power on your clicker
• When autoscan begins, press to stop it
• Press to display the Setup Menu
• Scroll up to display the ID menu option
• Press enter (green arrow) to select it
• Input your Student ID No Alpha Characters, No
  Leading Zeros!!!
• Press the left arrow to backspace if you make an
  error
• G. If correct, press enter (green arrow) to save
  your Student ID
• H. You may shut off the PRS or Press and enter
  (green arrow) to scan for classes

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PRS Example

• Enter class letter (or number) then enter
• Question In order to do well in Physics I, you
  should spend how many hours working on Physics I
  material for every hour in class (recitation and
  lecture)?
• A) 0-1 HRS
• B) 1-2 HRS
• C) 2-3 HRS
• D) 3 HRS

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Standard Homeworks

• Homework assignments online at course website
  (http//faculty.uml.edu/dwasserman/95.141.htm)
• Most weeks, the written HW is due on Friday
  (there are 2 weeks when the HW is due Wed.).
• There will be a box in the Physics front office
  where you can turn your HWs in. HWs will be
  returned in section within 1 week.
• HWs must have NAME and SECTION !!!
• Please follow the HW guidelines in the syllabus.
• Graded out of 10, total 90/750 of your final
  grade
• Late homeworks not accepted.
• Homework review sessions for EVERY homework set.

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Lecture Prep Homeworks

• These HWs are designed as review of the previous
  lecture, and are due before each lecture.
• Usually consist of 2-3 tutorials. You have
  unlimited attempts to answer.
• Use these as a study guide to keep you up to
  speed with lectures.
• Count for 20 pts over the course of the semester
• DONE ONLINE!!!!
• www.masteringphysics.com
• Course WASSERMANS10
• Instructions can be found on website for
  accessing masteringphysics.com

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www.masteringphysics.com
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www.masteringphysics.com
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Quizzes

• Given by recitation instructor, during
  recitation.
• 90/750 of Final Grade.
• No remakes. (for excused absences, recitation
  instructor can drop missed quiz).
• Normalized to class quiz average (a tough
  recitation instructor doesnt hurt your final
  grade!)
• Should cover material from previous weeks
  class/recitation.

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EXAMS

• 3 Mid-Term Exams
• Each worth 100 pts.
• Taken in class.
• Each covers lectures from previous exam up to
  exam date
• No rescheduling
• Extra time available for students with
  disabilities (must have note from Office of
  Student Disabilities)
• Final Exam
• 200 pts.
• Date/Time/Location To Be Announced

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EXAM 0

• There will be an Exam 0 in class on Wednesday.
• Exam 0 counts for 20 pts.
• This is a test of very basic math skills and the
  contents of Lecture 1 and Chapter 1.
• This is meant to be a tool for you
• It will give you a chance to see where your
  quantitative skills stand, to see whether you are
  prepared for this very challenging course.
• The difficulty level of Exam 0 is not indicative
  of the types of exams I give!!

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Physics I Resources

• Need to get help as soon as you feel like you may
  be falling behind!
• The first person to contact if you are having
  problems with Physics I is your Recitation
  Instructor!!
• Recitation Instructors will have office hours
  each week during which they can meet.
• HW review sessions
• UML tutoring center information on course
  website (http//faculty.uml.edu/dwasserman/95.141.
  htm)

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Fun ? Easy

• We have worked very hard to make this course fun
  and interesting!
• But this does not mean the course will be easy.
• This stuff matters!!
• 1hr in class 3 hrs outside of class
• You will have to work hard to do well in Physics
  I.
• You will have to be organized to do well in
  Physics I.
• You will have to come to class to do well in
  Physcis I.

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Physics I (95.141)
Lecture 0 OnlineBasic Trig., Calc. and other
mathematical concepts.Lecture 1 Chapter 1
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Chapter 1-3 Measurement and Uncertainty

• No measurement is perfectly precise
• For any measurement, it is important to give the
  uncertainty in the measurement
• Either in absolute numbers 0.1g or 0.2mm, for
  example
• Or in percentage 10m /- 2, or 3.2kg /- 10

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Chapter 1-3 Measurement and Uncertainty

• If uncertainty is not explicitly mentioned, we
  assume it to be 1, or a few units in the last
  digit specified
• The speed of the car was 51.2 mph
• Means
• The speed of the car was 51.2 mph /- 0.1mph

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Significant Figures

• Significant figures the number of reliably known
  digits in a number
• 45.21 kg ? 4 significant figures
• 0.00495m ? 3 significant figures
• If you are making a measurement, be careful about
  how many digits you use!!
• i.e. I am 6 ft 4.23457 inches
• Scientific Notation
• 4,560,000,000 ? 4.56 x 109

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Chapter 1-4 Units

• Units are important!!!
• If I am bragging about my weight
• I weigh 150!
• Could mean
• I weigh 150lbs
• Or.
• I weigh 150kgs
• In Physics we try to use the same set of
  unitsSI Système Internationale

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Chapter 1-4 SI Units

• Length meters m
• Time seconds s
• Mass kilogram kg
• Temperature K
• For dealing with very small or very large
  numbers, we can make use of prefixes

• G?giga?109
• M?mega?106
• K?kilo?103

• m?milli?10-3
• µ?micro?10-6
• n?nano?10-9

• 100,000m can also be written as 100 kilometers
  (km)
• 0.0001s could be written as 100 microseconds (µs)

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Chapter 1-4 Converting Units

• Sometimes we dont get problems in the units we
  like
• Two cars are traveling on the highway, car 1 at
  55mph, car 2 travels 200m in 10s. Which is going
  faster?
• Need to convert between mph and m/s ? conversion
  factor
• Car 1
• Car 2

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Chapter 1-6 Estimating

• Why is estimating important?

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Chapter 1-6 Estimating

• Being able to make order of magnitude estimates
  is an important skill!!

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Chapter 1-6 Estimating (Fermi Problems)

• What is the capacity of this room?
• Could try to count every chair
• Or could make a quick estimate

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Chapter 1-6 Estimating (Fermi Problems)

• How many barbers/salons should a town of 300,000
  people have?

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Chapter 1-7 Dimensional Analysis

• Dimensions of a quantity refer to the units that
  make it up
• Speed ? L/T, i.e. m/s
• Acceleration ? L/T2, i.e. m/s2
• We can learn a lot simply by looking at the units
  involved in an expression.
• If someone tells you that the speed of a car is
  given by the following expression

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Chapter 1-7 Dimensional Analysis

• Later in the semester, we will learn that Force
  has the units of Newtons N
• Fma
• FgGM1M2/R2
• What are the Units of G-Universal Gravitational
  Constant?