12/93/2013PHY 113 C Fall Lecture 251 PHY 113 C General Physics I 11 AM – 12:15 PM MWF Olin 101 Plan for Lecture 25: 1.Comments on Exam 3 2.Pep talk on preparing for Final Exam 3.Comprehensive review – Part I  Bonus attendance points for Lecture 26 – Part II of comprehensive review & course assessment

12/93/2013 PHY 113 C Fall Lecture 252

12/93/2013PHY 113 C Fall Lecture 253 Final exam schedule for PHY 113 C

12/93/2013PHY 113 C Fall Lecture 254 Comments on Final Exam  It will be comprehensive (covering material from Chapters 1-22)  It is scheduled for 9 AM Dec. 12 th in Olin 101  In class format, but there will be no time pressure  May bring equation sheets according to your vote

12/93/2013PHY 113 C Fall Lecture 255 Comments on Exam 3 iclicker question Which of the following statements matches your recollections of the exam: A.It was too hard B.It was too easy C.The Thanksgiving holiday erased all recollections of the exam Solutions are now posted:

12/93/2013PHY 113 C Fall Lecture 256 Two versions of take-home portion of exam

12/93/2013PHY 113 C Fall Lecture 257 Take home portion of Exam 3 -- continued

12/93/2013PHY 113 C Fall Lecture 258 Take home portion of Exam 3 -- continued

12/93/2013PHY 113 C Fall Lecture 259 Take home portion of Exam 3 – continued Two problems with question: 1.Round-off error in adiabatic step 2.Error in Lecture 21 notes (now corrected)

12/93/2013PHY 113 C Fall Lecture 2510 Work done on a system which is an ideal gas: “Adiabatic” (no heat flow in the process process) P (1.013 x 10 5 ) Pa PiPi ViVi VfVf Q i  f = 0 For ideal gas: PV  = P i V i  Corrected equations from #21:

12/93/2013PHY 113 C Fall Lecture 2511 Further comments on adiabatic processes

12/93/2013PHY 113 C Fall Lecture 2512 Take home portion of Exam 3 -- continued

12/93/2013PHY 113 C Fall Lecture 2513 iclicker question This problem A.Of all the problems that might appear on the final exam, this one would be the worst. B.Of all the problems that might appear on the final exam, this one would not be the worst. C.This example has inspired me to look into designing better engines or heat pumps.

12/93/2013PHY 113 C Fall Lecture 2514 In-class portion of Exam 3

12/93/2013PHY 113 C Fall Lecture 2515 In-class portion of Exam 3 -- continued toward away

12/93/2013PHY 113 C Fall Lecture 2516 In-class portion of Exam 3 -- continued VSVS f’=560 Hz VSVS f’=480 Hz

12/93/2013PHY 113 C Fall Lecture 2517 VSVS f’=560 Hz VSVS f’=480 Hz

12/93/2013PHY 113 C Fall Lecture 2518 In-class portion of Exam 3 -- continued

12/93/2013PHY 113 C Fall Lecture 2519 In-class portion of Exam 3 -- continued FBFB mg

12/93/2013PHY 113 C Fall Lecture 2520 In-class portion of Exam 3 -- continued iclicker question A.This density seems correct. B.This density seems wrong.

12/93/2013PHY 113 C Fall Lecture 2521 In-class portion of Exam 3 -- continued

12/93/2013PHY 113 C Fall Lecture 2522 In-class portion of Exam 3 -- continued

12/93/2013PHY 113 C Fall Lecture 2523 Back to the discussion of the Final exam: iclicker question What is the purpose of the Final Exam? A.Pure pain and suffering B.Assessment of student learning C.Gateway to medical school or other professional career D.Help students to “solidify” knowledge of physics and further develop problem solving skills E.All of the these

12/93/2013PHY 113 C Fall Lecture 2524 iclicker question How many equation sheets should you prepare for Final Exam? A.0 B.1 C.2 D.3 E.4

12/93/2013PHY 113 C Fall Lecture 2525 General advice on how to prepare for Final Exam  Review fundamental concepts and their corresponding equations  Develop equation sheet(s) that helps you solve example problems on all of the material. You can assume that empirical constants and parameters will be given to you; they need not take up space on your equation sheet.  Practice problem solving techniques.  If you discover unanswered questions, please contact me.

12/93/2013 Advice: 1.Keep basic concepts and equations at the top of your head. 2.Practice problem solving and math skills 3.Develop an equation sheet that you can consult. Equation Sheet Problem solving skills Math skills 26 PHY 113 C Fall Lecture 25

12/93/2013PHY 113 C Fall Lecture 2527 Problem solving steps 1.Visualize problem – labeling variables 2.Determine which basic physical principle(s) apply 3.Write down the appropriate equations using the variables defined in step 1. 4.Check whether you have the correct amount of information to solve the problem (same number of knowns and unknowns). 5.Solve the equations. 6.Check whether your answer makes sense (units, order of magnitude, etc.).

12/93/2013PHY 113 C Fall Lecture 2528 Specific review material -- standing sound waves General wave equation: wave propagation distance time wave speed

12/93/2013PHY 113 C Fall Lecture 2529 Specific review material -- standing sound waves Periodic wave: Periodic traveling waves: Amplitude wave length (m) period (s); T = 1/f phase (radians) velocity (m/s)

12/93/2013PHY 113 C Fall Lecture 2530 “Standing” wave: Combinations of waves (“superposition”)

12/93/2013PHY 113 C Fall Lecture 2531 Specific review material -- standing sound waves open-open open-closed y(x,t) is density fluctuations in the air v=v sound  343 m/s

12/93/2013PHY 113 C Fall Lecture 2532 Specific review material -- standing string waves (which can couple to sound) L

12/93/2013PHY 113 C Fall Lecture 2533 iclicker question How can we hear a standing wave on a string? A.The string couples to the air to produce a sound wave at the same wavelength B.The string couples to the air to produce a sound wave at the same frequency C.You cannot hear a standing wave on a string

12/93/2013PHY 113 C Fall Lecture 2534  Bonus attendance points for Lecture 26 – Part II of comprehensive review & course assessment  Bonus points for ing in questions you would like to discuss in Lecture 26