The 4

th

Edition of Matter & Interactions

Ruth Chabay Bruce Sherwood Department of Physics North Carolina State University

Wiley Workshop, AAPT winter meeting, San Diego, 2015-01-04

Matter & Interactions 4e

R. Chabay & B. Sherwood

John Wiley & Sons

• • Contemporary introductory calculus-based physics course for engineers and scientists Current users include: • Large institutions: Purdue, Georgia Tech, NC State, U of Texas Austin, Cal State Long Beach, Carnegie Mellon; others with honors courses • Four-year colleges, including Carleton, Wellesley, Haverford, Union, St. Olaf, and others.

• • Some community colleges, a few high schools Outside the U.S.: University of Calgary (Canada), Monterrey Tec (Mexico), Chalmers University (Sweden), University of Cape Town, Australian National University, Macquarie University (Australia), University of Helsinki; • Spanish version (3e) in press (Trillas, Mexico)

20

th

century: Flood of new information

Atoms have massive nuclei. Electrons surround nuclei.

Specific heat capacity varies with T at low temperature Energy is quantized Mass is energy Superconductors have zero resistance Particles are waves. Waves are particles. Everything is fields.

p + , p , p 0 , m + , m , D + , D ++ , t, K, W, n...

Time runs differently in moving frames

How did physicists cope with this information influx?

• Parsimony and unification • Small number of fundamental principles (Conservation laws) • Small number of fundamental interactions (electromagnetic, strong, weak, gravitational) • Small number of kinds of particles (quarks and leptons)

What might a contemporary intro physics course look like?

• Emphasize a small number of fundamental principles instead of a large number of derived formulas • Integrate the atomic nature of matter from the start • Engage students in making models of physical phenomena, based on fundamental principles (computation is an essential component)

Modern Mechanics

• The Momentum Principle • The Energy Principle • The Angular Momentum Principle • Randomness and Entropy

Matter in Mechanics

• The Momentum Principle • springs; gravitating masses; protons, electrons, neutrons; four fundamental interactions • ball-spring model; Young’s modulus; speed of sound in a solid; introduction to friction; gases; Tarzan and the vine • discovery of the nucleus • The Energy Principle • nuclei (mass, fission, fusion) • heat capacity; internal energy; dissipation • electronic energy levels; diatomic molecules • energetics of extended systems; details of friction • The Angular Momentum Principle • Bohr model; particle spin • Randomness and Entropy • Einstein model of a solid; constant-temperature atmosphere; speed distribution in a gas; specific heat of diatomic molecules

Electric & Magnetic Interactions

• Stationary charges • Electric field; superposition • Moving charges • Electron and conventional current; magnetic field • Magnetic force • Charge and field in circuits • Patterns of field in space • Gauss’s law and Ampere’s law • Time-varying charge motion • Faraday’s law • Maxwell’s equations; electromagnetic radiation

Matter in E&M

• Electric field • Electron mobility • Polarization of conductors and insulators • Circuits • Drude model; electron current; surface charge • Magnetic field and magnetic force • atomic models of ferromagnetism • Hall effect; motional emf • Electromagnetic radiation • effect of electromagnetic radiation on matter; re radiation; index of refraction

It’s too hard…

• Not for students.

• But it is unfamiliar to first-time instructors, especially those who have taught the traditional approach for some time.

It’s too easy…

What About Coverage?

• If you start from fundamental principles: • “Special cases” are not special • Topics traditionally seen as unrelated are unified • Students can analyze novel phenomena that aren’t explicitly taught

What’s new in the 4

th

edition?

General issues

• More problems • More WebAssign problems • More computational problems • Improved indication of problem difficulty • Cleaner page layout • Answers to odd-number problems • Student solution manual (Aaron Titus and Joe Heafner) – a selection of odd-numbered problem solutions • Updated, extensive instructor resources

The Momentum Principle

• A new approach to the Momentum Principle

Now and Future: Curving motion (Ch 5)

4e Support for Computational Modeling

• Iterative calculations done by hand (a few steps) • Translation of algebra to VPython code • Focus on key program elements • Labs rewritten to coordinate with text • Emphasis on reading, modifying code • New VPython videos on lists • Extended Instructor Guide to Computation • Recurring comparisons of analytical and iterative solution approaches • Many additional computational problems, small and large

Translation of algebra to VPython code

Focus on key program elements

Focus on key program elements

Many additional computational problems, small and large

Point Particle vs.

Extended System

• Ongoing discussion of the relationship between modeling a system as a point particle or as an extended system

Other changes, by chapter

• We will highlight significant changes in specific chapters. In addition, in many chapters there is an improved sequencing of topics.

• Ch. 5: more instruction on multiobject systems; improved analysis of curving motion; dot product introduced to calculate parallel and perpendicular components of momentum, including computationally • Ch. 6: improved discussion of path independence, including the fact that it is valid only for objects that can be modeled as point particles • Ch. 7: choice of reference frame affects terms in the Energy Principle

• Ch. 8: randomness of emission; lifetime of an excited state • Ch. 9: improved analysis of point particle and extended system models • Ch. 11: more extensive treatment of rotational kinematics, with new homework problems • What was Ch. 13 on gases will be moved to the Wiley student site as Supplement S1

• Ch. 14 (effects of electric field on matter): we show in detail the computed distribution of surface charge on a polarized metal block in equilibrium • Ch. 15 (fields of distributed charges): explicit instruction on Python lists, for sets of source charges and for sets of observation locations • Ch. 18 (circuits in terms of charge and field): we show in detail the computed distribution of surface charge on various quasi-DC circuits Click here for surface charge demo

• Ch. 16 (electric potential): instruction on how to calculate potential difference computationally • Ch. 20 (magnetic force): corrected analysis of motional emf in the case of a bar moving along rails; updated “Jack and Jill” to “Alice and Bob” • Ch. 21 (patterns of fields in space): optional section on PN junctions will be moved to the Wiley student site as Supplement S2

The chapter on waves will be available on the Wiley student site as Supplement S3, with a new section on the wave equation and longitudinal and transverse mechanical waves, with micro and macro analyses

Matter & Interactions 4e R. Chabay & B. Sherwood John Wiley & Sons 2015 www.wiley.com/college/sc/chabay matterandinteractions.org