Printable Thermometer Worksheets by hxz72218

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									             Temperature




Physics 102
Professor Lee Carkner
Lecture 1
             Things to Know
Physics 102: Principles of Physics
Professor Lee Carkner
Thing you will need
  Giancoli, “Physics”, 6th edition
  Scientific calculator
     Bring both to class
  Lab manual
  WebAssign card
 Help session:
   TBA (Hopefully Tues, Thurs evenings)
Lab section
  If you need to add a lab or change labs, fill out lab
   form
  Labs start this Thursday!
   How Does the Class Work?
 Read the book material before class
    Do the WebAssign homework
 Before class
    Download and print out class notes
    http://helios.augustana.edu/~lc/ph102
    Be sure to set as “Pure Black and White”
 Come to class
    Do the PAL exercises
    Answer the Quizdom questions
 Lab once a week
 Three tests and final
                WebAssign
Homework will be entered and graded online
  At webassign.com
Click on student login
Username is your first and last name together
 (e.g. “johnsmith”)
Institution is “augustana”
Password is same as last semester
  Augustana ID number if new to class
After login, click on the current assignment and
 complete it
  WARNING: Can only submit it three times
               Homework
Homework will generally be from book
  Will be posted on webpage if you want to look at
   them without a computer
  WebAssign will randomize numbers
Available at noon M,W,F
Due at midnight Tue, Thu, Sun
  Cannot turn homework in late or make up
  Can drop lowest three
Each homework worth same amount (100
 points)
  10% of grade
  Can drop (or miss) three
  No make-ups or grade changes
                  PAL
What is PAL?
  Physics Active Learning
Each class you will get a PAL
 worksheet
Also will answer questions with
 Quizdom remotes
Worth 15% of your grade
  Need to come to class
  Can drop (or skip) three PAL’s
  Grading on Tests and PALs
1. Written answers must be in complete
   sentences
2. Numbers must have units
3. Answers must reasonable
  • If not reasonable, explain why
4. All work must be neat and easily
   readable
        Thermodynamics
What is thermodynamics?
  Thermo
    
  Dynamics
    
Thermodynamics is the study of
 thermal and mechanical energy
  How do you transform one into the other?
Where Does Thermodynamics
       Come From?
Back in the early 1800’s people figured
 out that you can transform thermal into
 mechanical energy


  A heat engine
Problem:

  Need to understand what is going on in
   the engine
                  Temperature
How does temperature manifest itself?


    e.g., the height of a column of fluid


    We still don’t know what temperature is
            Thermal Equilibrium


    A thermoscope
Now put the thermoscope in a cup of water


    They are not transferring heat
    They are at the same temperature
Two bodies at different temperatures placed
 together will exchange heat until they are in
 thermal equilibrium (and thus at the same
 temperature)
Zeroth Law of Thermodynamics


                      or
if a thermoscope placed near one and then the
 other reads the same
Zeroth Law of Thermodynamics
    If two objects are each in thermal equilibrium with
     a third object then they are also in thermal
     equilibrium with each other
                  Thermometers
In order for a thermoscope to be a
 thermometer it needs to be calibrated
Example: the Celsius scale
    
    Put it in ice and mark the height of the column as 0
    

    Fill in the numbers 1-99 (in even intervals) in
     between

       Only tells you temperature relative to the freezing point
        of water
      Types of Thermometers
 Glass tube                      Dial
    Physics: Increase of            Physics: Increased bending
     length with increasing           of bi-metal strip with
     temperature                      temperature
    Pros:                           Pros:
                                     Cons:
    Cons:                        Radiation
 Resistance                         Physics: Change in type
    Physics: Electrical              and amount of radiation
     resistance increases with        emitted with temperature
     increasing temperature          Pros:
    Pros:
                                     Cons:
    Cons:
         Temperature Scales
Gabriel Daniel Fahrenheit invented the
 mercury thermometer in 1714
  


Anders Celsius introduced his scale is 1742
  


William Thomson, Lord Kelvin, determined
 from theory that minus 273.15 degrees
 Celsius is the coldest it can get
             The Kelvin Scale
In science we normally use the Kelvin scale
    
    Tells you temperature relative to absolute zero,
     the coldest anything can get


    No negative numbers


               TC = TK -273.15
               TF = 9/5 TC +32
A temperature change of 5 Celsius degrees is
 equal to a temperature change of 9 Fahrenheit
 degrees
        Thermal Expansion
Heating an object causes it to expand


Why?
  

The degree of expansion depends on the
 change in temperature and the coefficient of
 expansion
  We can measure temperature and look up
   coefficient of expansion
          Linear Expansion
The degree to which the length of an object
 changes is given by:
                  DL = L a DT
Where a is the coefficient of linear expansion
This applies to all dimensions of a solid
 length, width and height
Change in length is proportional to length
 and temperature change
If the linear dimensions of a solid change then
 the volume must change:
                  DV = V b DT
   Where b=3a
        Thermal Expansion and
            Thermometers



Consider two strips of metal with different
 coefficients of linear expansion attached
 together (bimetal strip)
    

This principle is used in dial thermometers
 and thermostats
               Next Time
Read: 13.4, 14.3-14.4, 14.6-14.8
Homework: CH 13, P 9, 10, 11, CH 14: 9,
 33
  Due midnight before class
Note that you might have to look up
 values in the textbook
Watch units!

								
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