# Physics 252: Modern Physics

(as given in Spring 1999)

### Teacher: Michael Fowler

(For premodern physics, check out my course on Galileo and Einstein.)

For German Readers: All the lectures below on Special Relativity have been translated into German by Christoph Scholz, who teaches high school physics (pupils aged 10-19) in Hagen, Germany. They can be downloaded in pdf format at einstein-deutsch.pdf

Scholtz’ school URL is http://www.ha.shuttle.de/ha/hildegardis/mint/physik.htm

These notes are copyright. Students can make one copy for personal use, but the notes are not to be distributed commercially without permission of the author and the translator.

## Index of Lectures

### Special Relativity

12 lectures
Galilean Relativity and the Invariance of Newton's Laws.
The Speed of Light
The Michelson-Morley Experiment.
Special Relativity
Time dilation and length contraction.
The relativity of simultaneity.
The Lorentz transformations.
A worked example of time dilation.
The twins and other paradoxes, and the Doppler effect.
Velocity Addition.
Relativistic dynamics: mass, relativistic momentum and energy.
Equivalence of mass and energy: Einstein's Box.
Relativistic energy-momentum formula.
Particle Creation.
Electric and Magnetic fields in Relativity.
Remarks on General Relativity.

Brief Review of the Kinetic Theory of Gases

### Photons

4 lectures
Blackbody Radiation.
The Photoelectric Effect.
Rays and Particles.

### Atoms

6 lectures
Brief Historical Review.
Atomic Spectra
Early Atomic Models: Vortices and Pudding
Rutherford's Experiment and the Beginning of Nuclear Physics.
The Bohr Atom.

### Particles and Waves

4 lectures
From the Bohr Atom to De Broglie's Waves.
Wave Packets and the Uncertainty Principle.
Probabilities, Amplitudes and Probability Amplitudes.
More on the Uncertainty Principle.

### Schrodinger's Equation

6 lectures
Wave Equations for Photons and Electrons.
Electron in a Box.
Finite Square Well
Simple harmonic oscillator.
Barrier penetration.
Two-dimensional Wells.
Three dimensional waves,the hydrogen atom, angular momentum.

### Many Electron Atoms

3 lectures
Symmetry of the wavefunction: fermions and bosons.
Angular Momentum, Electron spin, The periodic table.

### Nuclear Physics

3 lectures
Stable and unstable nuclei, decay mechanisms, nuclear fission.

## Homework Assignments

Due Friday, January 29: French, Special Relativity, Chapter 2: 5, 6, 7.

Due Friday, February 5: French, Special Relativity, Chapter 4: 1, 3, 5, 11, 14.

Due Friday, February 12: French, Chapter 4: 9, 10. Ch. 5: 7, 9, 11.

Due Friday, February 19: French, Chapter 4: 12, 13(a), 18, 19. Ch. 5: 16, 20, 22. Ch 6: 7.

Pledged Set 1 due Friday, February 26

Homework due Friday, March 5

Midterm Review Sheet

Midterm Exam

Homework due Friday, April 2

Homework due Friday, April 9

Homework due Friday, April 16

Pledged Set 2 due Friday, April 23

Notes on Complex Numbers

Final Review Sheet

Last Year's Final Exam

Spring 1999 Class