Chapter 1 This chapter presents a review of some topics fromclassical physics. I have often heard from instructors using thebook that my students have already studied a year of introductoryclassical physics, so they dont need the review. This reviewchapter gives the opportunity to present a number of concepts thatI have found to cause difficulty for students and to collect thoseconcepts where they are available for easy reference. For example,all students should know that kinetic energy is 212 mv , but feware readily familiar with kinetic energy as 2 / 2p m , which isused more often in the text. The expression connecting potentialenergy difference with potential difference for an electric chargeq, U q V = , zips by in the blink of an eye in the introductorycourse and is rarely used there, while it is of fundamentalimportance to many experimental set-ups in modern physics and isused implicitly in almost every chapter. Many introductory coursesdo not cover thermodynamics or statistical mechanics, so it isuseful to review them in this introductory chapter. I have observedstudents in my modern course occasionally struggling with problemsinvolving linear momentum conservation, another of those classicalconcepts that resides in the introductory course. Although wephysicists regard momentum conservation as a fundamental law on thesame plane as energy conservation, the latter is frequently invokedthroughout the introductory course while former appears andvirtually disappears after a brief analysis of 2-body collisions.Moreover, some introductory texts present the equations for thefinal velocities in a one-dimensional elastic collision, leavingthe student with little to do except plus numbers into theequations. That is, students in the introductory course are rarelycalled upon to begin momentum conservation problems with initialfinalp p= . This puts them at a disadvantage in the application ofmomentum conservation to problems in modern physics, where manydifferent forms of momentum may need to be treated in a singlesituation (for example, classical particles, relativisticparticles, and photons). Chapter 1 therefore contains a briefreview of momentum conservation, including worked sample problemsand end-of-chapter exercises. Placing classical statisticalmechanics in Chapter 1 (as compared to its location in Chapter 10in the 2nd edition) offers a number of advantages. It permits theuseful expression 3av 2K kT= to be used throughout the text withoutadditional explanation. The failure of classical statisticalmechanics to account for the heat capacities of diatomic gases(hydrogen in particular) lays the groundwork for quantum physics.It is especially helpful to introduce the Maxwell-Boltzmanndistribution function early in the text, thus permittingapplications such as the population of molecular rotational statesin Chapter 9 and clarifying references to population inversion inthe discussion of the laser in Chapter 8. Distribution functions ingeneral are new topics for most students. They may look likeordinary mathematical functions, but they are handled andinterpreted quite differently. Absent this introduction to aclassical distribution function in Chapter 1, the students firstexposure to a distribution function will be 2, which layers anadditional level of confusion on top of the mathematicalcomplications. It is better to have a chance to cover some of themathematical details at an earlier stage with a distributionfunction that is easier to interpret.
Problem Solutions For Introductory Nuclear Physics By Kenneth S. Krane [PATCHED]
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