ChemPhys 273 - Semester Review

First Semester, 2013-2014

Background Information

The physics exam for ChemPhys 273 will be held during the week of January 13 - affectionately known as "Finals Week." The exam will be a 90-minute exam covering all topics learned during the first semester. The exam will be started the moment the exam period begins and will be collected at the end of the 90-minute exam period; extra time will not be alloted. If there are special circumstances that require that you need additional time, then see Mr. Henderson privately before the day of the exam to discuss those circumstances; unless such arrangements have been made in advance of exam day, no extra time will be given.

Most of the questions are multiple-choice (approx. 75); there are approximately 10 problems to solve. Many of the multiple choice questions include up to 10 possible choices - from a through e and such choices as ab, ac, ad, etc. Planning to guess on questions is unlikely to be a wise alternative to planning to prepare. The exam answers will be placed on GradeMaster forms. Each section will have a separate form of the exam with nearly identical or at least very similar questions. The exam is not likely to be curved; it would not be surprising if there were a few perfect or near-perfect scores. Your exam score in physics will be averaged with your exam score in chemistry. This averaged score will comprise 20% of your semester grade in ChemPhys.

Contents of Exam

There are ~90 multiple choice questions on the final exam and ~8 problems. The multiple choice questions cover the following topics:

 Topics Approx. # of Qs Newton's Laws and Their Applications: Newton's first law - concept of inertia; relationship to mass Newton's second law - factors affecting acceleration; meaning of net force; simple computations Newton's third law - action-reaction; identifying force pairs in an interaction Free-body diagrams and analysis - computing acceleration from known force values or determining an individual force value from a known acceleration Combining a = Fnet/m with kinematics Friction - static vs. kinetic; coefficient of friction; equation; determining Ffrict Air resistance, teminal velocityEquilibrium - definition/concept; analyzing static situations (e.g., hanging signs) Dynamic situations with forces at angles; SOH CAH TOA and a = Fnet/m Inclined plane problems - resolution of force of gravity; conceptual understanding; computations; analyzing to determine the acceleration Two-body problems - system analysis to determine acceleration; individual analysis to determine tension force or other forces ~33 Qs Circular Motion and Gravitation: Uniform circular motion - conceptual understanding of vector quantities - v, a, and Fnet; importance of inertia in understanding the sensation of a centrifugal pull (careful); centripetal force Simple computations of quantities such as v, a, Fnet, T, etc. Mathematical analysis of physical situations involving motion in circles; use of a = Fnet/m and free-body diagrams to solve problems Newton's law of universal gravitation - universal nature of gravity; conceptual understanding of the m-d-F relationships; simple computations Satellite motion - variables effecting T, v, a, Fnet; role of gravity Kepler's laws and their use to describe planets and other satellites Weightlessness - conceptual understanding of the cause of this sensation ~22 Qs Static Electricity: Charge interactions between like- and opposite-charges, etc. Conductors vs. insulators Methods of charging objects - friction, conduction (contact) and induction Grounding Polarization Electric force and Coulomb's law calculations Electric field - definition/concept, equation, units, simple computations Electric field lines (SKIP for 2013-2014 exam) Lightning rods and electric fields (SKIP for 2013-2014 exam) ~22 Qs Work and Energy: Work - concept, meaning, + or - or 0, units, formula and calculations Power - concept, meaning, formula, units, calculations ~3 Qs Science Reasoning: This includes specific passage-based questions as well as questions that are sprinkled throughout the test in which science reasoning (and not memorized information) is used to answer the question. Interpolating and extrapolating from data and graphs Identifying conclusions that are consistent with presented data Identifying simple and complex relationships from presented data Combining info from two or more data presentations (graph, data table, diagram) Using a simple or complex relationship to make a prediction Predicting the result of an additional trial in an experiment Analyzing an experiment to identify the dependent and independent variables, the assumptions, and the error involved Extending the conclusions of an experiment in order to make a prediction regarding a new situation Etc. Etc. ~10 Qs

Several of the questions require the use of a calculator; complex analysis are not common. Many quantitative questions are accompanied by a diagram - e.g., a free-body diagram - which forms the basis of the computation. When a calculation is involved, it is usually a straight-forward calculation (there are very few blue problems). Lots of questions can be answered quickly. Many questions are easy to very easy, others are of medium difficulty, few (if any) are complex, and none are impossible. The questions are much more general than what you would normally find on unit tests; small nuances are not the focus of the exam. Keep in mind that all questions are worth the same number of points. So do not blow 10 minutes trying to solve a two-body problem at the expense of other easier questions. If such a problem is that difficult for you, then count it as a loss and continue on with those questions which you do know. Return to the troublesome questions at the end of the test.

The following math equations will be provided on the test:

 d = [(vi + vf) / 2] • t d = vi • t + 0.5 • a • t2 vf = vi + a • t vf2 = vi 2 + 2 • a • d Fnet = m • a Fgrav = m • g Ffrict = mu • Fnorm SOH CAH TOA a = v2/R Fgrav = G • M1 • M2 / d2 G = 6.67 • 10-11 N•m2/kg2 g = G • M / R2 v = SQRT (G • M / R) T2/R3 = k Felect = k • Q1 • Q2 / d2 k = 9.0 • 109 N•m2/C2 E = F / q E = k • Q / d2 Qelectron = -1.6 • 10-19 C Fparallel = m • g • sine(theta) Fperp = m • g • cosine(theta)

How to Prepare

There are numerous ways to prepare for the test. The best ways are those which help you learn the material. This will be different for differnt learners with different learning styles. The main thing is to devote some time to the preparation process. There are numerous preparation tasks which can be done, all of which should help. The following provides some ideas:

• Use the Unit Review sheets from The Review Session for each of the four units which we have completed.
• Review old quizzes (but do note that there are many topics on the final which were not on quizzes).
• Use The Physics Classroom or the Multimedia Physics Studios to review topics which you have difficulty with or merely need to review.
• Utilize Minds On Physics to help prepare. Try any module you wish; there is no need to submit codes to the database.
• Review concept sheets from the packet and sample problems done in class.
• Review sections of your book and use the Reading Sheets from the packet to assist in your review.
• Review the major types of calculations that are performed with the equations listed above.
• Never under-estimate the power of a good night's sleep on the evening before an exam. This may mean that you will have begin preparations several days in advance.

Some absolute imperatives include:

• Know what each symbol in the given equations stand for; questions about what a symbol means or represents will not be answered on the test.
• Have a strong idea of what each type of problem might look or sound like and of how to analyze it. When the problem appear, you will need to have an instant understanding of how to approach the problem and of what equations to use. (For instance, you ought to know what a two-body problem looks or sounds like; and you ought to know that there are always two questions which are asked; and finally, you ought to be familiar with the problem solving approach. When it shows up, you can quickly procede with your strategy to answer the two questions.)