Physics discoveries video

From Youtube a Discovery video (45 min) about major physics discoveries. Good for discussion.

Vortex engine

Here is an interesting and intriguing topic which involves a lot of physics some of which is fairly basic. Perhaps good for an assignment? Cannot say how practical it is but looks impressive.

"AVEtec is the brainchild of Canadian engineer, Louis Michaud. His Atmospheric Vortex Engine (AVE) harnesses the physics of tornados to produce extremely cheap and clean energy. In his design, warm or humid air is introduced into a circular station, where it takes the form of a rising vortex, i.e. a controlled tornado. The temperature difference between this heated air and the atmosphere above it supports the vortex and drives multiple turbines. The vortex can be shut down at any time by turning off the source of warm air."

Using X-rays to identify minerals on Mars

The Mars rover (Curiosity) is using X-rays to identify the elements in rocks on Mars according to a report in Universe Today.
"...uses X-ray diffraction, the standard practice for geologists on Earth using much larger laboratory instruments, and this is the first time this method has been used on another planet. It provides more accurate identifications of minerals than any method previously used on Mars. X-ray diffraction reads minerals’ internal structure by recording how their crystals distinctively interact with X-rays."

"We now know it is mineralogically similar to basaltic material, with significant amounts of feldspar, pyroxene and olivine, which was not unexpected. Roughly half the soil is non-crystalline material, such as volcanic glass or products from weathering of the glass."

Looks like a good item to use in class as an example of diffraction or use of X-rays.

Atomic-scale devices

Devices such as electronic components and computer memory are being made from single atoms or a small number of atoms according to this report. Plenty of good physics involved in this. Major technology changes are on the way. Physics and electronics course will have to be revised. Lab work will be more of a challenge...

Thermoelectric electricity generation

The thermoelectric effect ususally gets a brief mention in A-level syllabuses (syllabi). This effect occurs in some materials where a temperature difference produces a potential difference. It is not often used to generate power since the efficiency is low, much less than using,say, a steam driven generator. It is also used in temperature sensors which can be small and robust.
Now progress has been made and a new material found with a much higher efficiency of 15-20% which make it much more useful. See this report from Phys.Org.

Satellite launch

Excellent look at the whole process of assembling the satellite launcher and launching. Features the space centre in French Guiana. A 1 hour program.

The Higgs particle

The more-or-less confirmed discovery of the Higgs particle must be noted as it is of major significance to Physics. See BBC reports here and here. While this development is not a surprise it provides major confirmation of the standard theory of matter (in terms of sub-atomic particles anyway), provides new insights and will lead to new progress in the years to come.

It might be compared somewhat with Rutherford's experiment which confirmed the existence of the atomic nucleus and stimulated many further developments.

I will not attempt to explain what the Higgs particle is - try the above reports for that. But be warned that there is no simple description!

Online electronics course from MITx

MIT has long been in the forefront of online education and open learning. They have now, with Harvard University, launched MITx with a free online course on electronics. See this report.
It looks to be of great value to those living where there are no accessible local equivalents. It is a university level course and hard work will be required! Definitely of interest to those doing Physics at A-level or university.

Physics free textbooks online

Given the current high costs of university textbooks I decided it would be useful to see what was available online in a open format. In this first post four general texts are considered which might be suitable for the first year or two at our University at least as supplementary material. These texts were found in these two lists of free texts:

http://www.e-booksdirectory.com/physics.php - a useful long list of some 200 free books and lecture notes, mostly university level
http://www.freebookcentre.net/Physics/Physics-Books-Online.html - many books categorised by topic, quite a few are also on the above list

The four texts are not easily compared as the styles are different as is the coverage. Some have additional downloads of teaching materials, some include exercises in the text. I have tried to give brief details of each and have included snapshot of their summary of Maxwell's Equations, if covered, to give an idea of the style. Also included at the end is one from Wikipedia for comparison.

In addition to these there are many collections of lecture notes, lecture videos etc which are difficult to assess.

Calculus-Based Physics by Jeffrey W. Schnick, Ph.D. of Saint Anselm College - mechanics, waves, fluids, heat, E&M, optics (no electronics or modern physics) split into two sections plus various other materials. 300+ pages. Creative Commons license. Multiple formats, PDF ~2 Mb per section. Dated 2008.

Essential Physics by Emeritus Professor Frank Firk of Yale University - intensive introduction to classical and special relativity, Newtonian dynamics and gravitation, Einsteinian dynamics and gravitation and wave motion, all in one file. ~210 pages. No copyright notice. PDF only 1Mb.
Note: does not cover Maxwell's Equations. Dated 2000.


Simple Nature by Benjamin Crowell, Ph.D. of Fullerton College - "calculus-based physics textbook meant for the type of freshman survey course taken by engineering and physical science majors", covers the topics usual for this level of Physics, split into 18 sections. ~900 pages total. Creative Commons license. Online and PDF 5 Mb per section. Dated 2012.

Modern Physics - A series of online books covering Waves, Mechanics, Special Relativity, Quantum Mechanics, Gravity, Electromagnetism, Thermodynamics and Nuclear Physics. Wikibooks

And here is the summary from Wikipedia (note the similarity to the Wikibooks text):

Faster CT scans

CT scanners are a key medical physics application and figure prominently in A-level syllabuses so this report should be of interest. After years of work by GE and Intel new software has been developed which speeds up the processing of an "image from a low-dose CT scan down from 100 hours per image to less than 1 hour" - a remarkable achievement. There are important safety implications since low-dose scans become more practical as a result. Also of interest is the use of parallel processing.

"It takes lots of time, and huge amounts of computing power, to turn the smaller dataset from a low-dose scan into a usable medical image. We're talking not hours but four to five days of computing time on mainframe-equivalent computers to come up with a workable image. For many doctors and hospitals, both the computer power needed and the long delay to get an image have made low-dose scans impractical."

"The joint team ultimately developed an accelerator based on 28 Xeon processors totaling 112 cores and a dramatically improved algorithm. We reduced the compute time to around an hour, delivering superior medical images and reducing the X-ray power by up to 90 percent."

Faster-than-light neutrinos - mistake?

It seems there may have been problems with the equipment - see this BBC report. Further results are expected in May. This underlines the need for scrupulous testing and for independent confirmation especially for research using equipment as complex as that used in this case.

Experiments in weighlessness on the ISS

One of NASA's astronauts has been doing some instructive and interesting experiments on the International Space Station described here.

"NASA and the American Physical Society (APS) have partnered to share unique videos from the International Space Station with students, educators and science fans from around the world. NASA astronaut Don Pettit will use everyday objects from Earth to demonstrate physics..."

The Earth - getting bigger or smaller?

This article from the BBC compares the ways in which the Earth is gaining and losing mass. It makes excellent discussion material for sixth form Physics students since it involves gravity, astronomy, mass-energy conversion and climate change all in one discussion!

"Using some back-of-the-envelope-style calculations, Dr Smith, with help from physicist and Cambridge University colleague Dave Ansell, drew up a balance sheet of what's coming in, and what's going out. All figures are estimated.

By far the biggest contributor to the world's mass is the 40,000 tonnes of dust that is falling from space to Earth, says Dr Smith."

Videos - cathode ray oscilloscope

Some useful links for CRO videos suitable for A-level or university from Youtube :

GCE (A-level) Physics E29 The Oscilloscope - YouTube 
Good clear introduction to basic CRO use mostly using diagrams. Examples of making measurements of voltage and frequency. 11mins

The Oscilloscope - YouTube  http://www.youtube.com/watch?v=5yNDSkQBEy0&feature=related
A good introduction to a more complex (dual-beam) CRO. The CRO is shown in action. 5mins

AC vs DC Explained and How to Use an Oscilloscope - YouTube 
Another look at basic CRO use using a real CRO and also using a CRO with a PC. 12mins