*Physics

"Science.gov searches over 60 databases and over 2,200 scientific websites to provide users with access to more than 200 million pages of authoritative federal science information including research and development results. "

"arXiv is a free distribution service and an open-access archive for 2,158,138 scholarly articles in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. Materials on this site are not peer-reviewed by arXiv. "

"Founded in 2002 by Nobel Laureate Carl Wieman, the PhET Interactive Simulations project at the University of Colorado Boulder creates free interactive math and science simulations. PhET sims are based on extensive education research and engage students through an intuitive, game-like environment where students learn through exploration and discovery."

"The SAO/NASA Astrophysics Data System (ADS) is a digital library portal for researchers in astronomy and physics, operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant.

The ADS maintains three bibliographic collections containing more than 15 million records covering publications in astronomy and astrophysics, physics, and general science, including all arXiv e-prints."

"This blog is intended for professional astronomers. The goal of AstroBetter is to provide information and tips about streamlining all the things we need to do astronomy well. Our discussions include computing, email management, paper organization, iPhone apps, and the like. In addition, we also provide methods for increasing productivity and efficiency in our self-directed work environment."

"HyperPhysics is an exploration environment for concepts in physics which employs concept maps and other linking strategies to facilitate smooth navigation. For the most part, it is laid out in small segments or "cards", true to its original development in HyperCard."

"The Unified Astronomy Thesaurus (UAT) is an open, interoperable and community-supported thesaurus which unifies the existing divergent and isolated Astronomy & Astrophysics thesauri into a single high-quality, freely-available open thesaurus formalizing astronomical concepts and their inter-relationships."

"Eos is the science news magazine published by AGU."

"The SIMBAD astronomical database provides basic data, cross-identifications, bibliography and measurements for astronomical objects outside the solar system."

Collection of various types of calculators, from math to finance to fitness.

Online conversions calculator for a variety of unit measurements featuring natural language queries.

Trigonometry, matrices, complex numbers, unit conversion and more.

"Physion is a free physics simulation software which allows you to design and simulate realistic physics experiments in a virtual physical world. You can think of it as a CAD application combined with a 2D physics engine where the objects you design can be instantly simulated."

physics open textbooks

"Founded in 1977 at Morgan State University, the mission of the National Society of Black Physicists is to promote the professional well-being of African American physicists and physics students within the international scientific community and within society at large"

"SASE is dedicated to the advancement of Asian heritage scientists and engineers in education and employment so that they can achieve their full career potential"