! Adapted from http://www.physics.ubc.ca/~janis/Courses/401/401topics.html >
Physics 401 Suggested Seminar Subjects
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Some Suggested Seminar Subjects
Remember, you are encouraged to come up with a topic of your choice not necessarily mentioned on this list... This list is to give you just a few ideas of potentially interesting topics. You may want to make your own variation of one the suggested topics below, or delve into an E&M related issue that has been on your mind already. For topics of a historical nature, many excellent references may be found online in electronic journals and at libraries on campus. I can provide some help with locating journal articles. I also recommend the UBC Library's free Research Skills workshop (offered several times per term) to learn how to approach a general research problem and familiarize yourself with many of the 'standard' online e-tools, including the Web of Science, the science citation index, how to get the most out of online databases, accessing electronic journals and e-books.
Want to browse for ideas? Get a current list of articles on from Scientific American on:
Nature, Popular Mechanics, Science, Discovery are popular appropriate-level for such presentations, as are a number of popular journals and academic physics journals, all available in several libraries on campus and online as Electronic Journals accessible to you from any on-campus site (....ubc.ca) or by using a proxy server, thanks to the UBC Library's sitewide e-journal licenses.
This is either the coolest technology ever or just another crank idea. You decide. (Usually crank ideas are easy to spot, but sometimes it takes real effort to discern their mistakes; I'd welcome a thoughtful critique of something that seems crazy but isn't obviously wrong.)
There are many cool space-type applications involving sweeping an electrodynamic tether through a magnetic field in space to generate large potential differences, which can be used for propulsion without huge masses of propellants.
Lightning is an amazing force and beautiful phenomenon in nature driven by interesting processes in the earth's atmosphere which generate huge potential difference between storm clouds and earth. How is lightning made?
For example: Electric Hurricanes (NASA, 09 Jan 2006).
Radar just uses radio-wave electromagnetic waves, but how does it work? Or how does the speed-trap radar that our friendly cops use work? (...how can you jam it?)
Particle Accelerators - cyclotron, or synchrotron, or betatron
Ernest Orlando Lawrence proposed the idea of a magnetic resonance accelerator (the cyclotron), and in the 1930's he and a graduate student, Stanley Livingston built and operated the first cyclotron. (It won Lawrence a Nobel Prize) Describe their apparatus and explain how it was used to accelerate protons to 1.2MeV. A modern synchrotron, such as the one at TRIUMF, is based on a principle similar to that of the cyclotron, except that the magnetic bending field, B, and the RF frequency must increase and be synchronized with the particle velocity as it increases. Outline briefly how the TRIUMF synchrotron (or any particle accelerator of your choice) works. A Betatron uses an alternating magnetic field to accelerate particles using magnetic induction (according to Faraday's Law).
This gorgeous natural phenomenon is just plasma physics (E&M). Go over the physics of the Aurora borealis. Under what conditions do we see them? What determines the colours?
Light interacting with water drops, dust or ice crystals in the atmosphere produces a host of beautiful spectacles - rainbows, halos, glories, sundogs, coronas among others. Select and explain one or more and describe how they form and the physics behind them. For example, rainbows are electromagnetic phenomena that rely upon the refraction of light. Explain the physics of rainbows and some of the subtle effects seen, for example primary and secondary bows, supernumerary bows, spokes and other interesting features.
Magnetic levitation is currently in use in Japan and in development elsewhere to levitate a train thus eliminating friction, enabling incredible ground speeds. Go over either the theory or technology of maglev trains.
A railgun can accelerate a projectile to high speed in a very short time. Such devices often figure in sci-fi novels as a means to launch stuff into space. Such a device can be use to launch payloads without carrying heavy fuel. You might remember rail guns from a not-so-popular movie starring the Governor of California.
Pick one or more bioelectric or biomagnetic living organisms and explain the physiological origin of electric and/or magnetic fields.
Electric and Magnetic fields in Nerve Cells
Cell membranes in general, and membranes of nerve cells in particular, maintain a small voltage or potential difference across the membrane. When nerve cells are stimulated, voltage across the membrane changes.... Just how do these things work?
What's in those little electronic tags that we get on some merchandise? How to they work? How are they deactivated by the checkout person?
Airport Security Metal Detectors
Those airport security metal detector gates make for annoying airport delays, but they likely increase our security. Most are based on a pulsed induction, with a transmitter on one gate and a receiver on the other side. How do they work? What are their shortcomings?
Your parents (and I) played with crystal radios in the pre-Nintendo era. How do they work? Want to make one and bring it in?
How do we use electromagnetic radiation in the radio wavelength range to heat up food and boil water so quickly? What processes go on in our food, why shouldn't you use metal in a microwave oven?
A plasma is an ionized gas consisting of free electrons and ions. Use a classical electron model to examine dispersion and conductivity in a plasma. Or present and explain some neat application of plasma physics.
Explain the theory and operating principles of transmission lines.
Rhythmic contractions of the heart pump blood occur in response to electrical control pulse sequences. Active cells in the sinoatrial node in the heart trigger a sequence of electrical events that control muscle contractions which pump the blood. How does this amazing electromagnetic bio-device work?
Particle Detectors, Drift Chambers
How do you make one? how does it work? How are they used to precisely measure momentum of the charged particles electron, muon, pion, kaon, and proton using the curvature of a particle's trajectory in a magnetic field (due to Lorentz force). Describe how measuring specific ionization (energy deposition per unit length traversed in a gas, often referred to as dE/dx) may be useful in identifying the 5 above mentioned particle species. Georges Charpak won the Nobel Prize for his invention and development of wire chambers.
Without Faraday, we'd have no Rock and Roll! How do an electric guitar's pickups work, and how to you drive a speaker?
Marconi and Radio Waves
In 1895, Guglielmo Marconi, a self-taught 21-year-old performed simple experiments that showed it was possible to send signals using electromagnetic waves to connect a transmitting and a receiving antenna. By 1901, he sent a wireless signal across the Atlantic. Review this discovery of radio.
What is it in an electric eel's anatomy that generates huge potential difference that can reach several hundred volts and deliver quite a shock?
Cell phones now let you talk with almost anyone anywhere on the planet, wirelessly! How do they work? What are all these different access technologies we hear about: PCS, GSM, CDMA and TDMA?? How does cell phone technology differ from say, walkie talkie technology?
Antenna Theory and Design
Review antenna theory and design an antenna for some specific or arbitrary purpose.
What are they? Can they fit into the electromagnetic theory of Maxwell? What experimental techniques have been used to search for them, and what are the results of these experiments?
Derive the potential and field of a relativistic charge in arbitrary motion. Show that the Coulomb potential is the limit when the charge is at rest and discuss some interesting aspects of this.
A pulsar is the remnant of a massive star that went supernova and now is a neutron star with a strong magnetic field, emitting radiation in a cone. How/Why do they pulsate? How do they get such huge magnetic fields?
Show that any vector field, for example the electric or magnetic field, can be decomposed into an irrotational part (curl is zero) and a solenoidal part (divergence is zero) and discuss implications and an illustrative example or two.
Review the classical model of dispersion, that is the frequency dependence of optical properties of materials.
Fresnel's four equations specify the reflected and transmitted amplitudes of electromagnetic waves at a smooth dielectric boundary. Go over the derivation of the equations and give some interesting insight into a physical system using them.
If you want to dive right into the deep end, consider the fact that Maxwell's equations are satisfied equally well by retarded potentials (see Ch. 10) or advanced potentials, which describe EM waves propagating backwards in time. In the 1940s, John A. Wheeler and his graduate student, Richard P. Feynman, proposed a "symmetrized" formulation in which both advanced and retarded potentials were equally in play but causality violation was hidden by a perfect reflection of the advanced wave off the Big Bang. (Or something like that.) Were they kidding? This would make a good science fiction novel!
Resources and Relevant Electronic Journals & Magazines