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