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):
