https://Physics-in-a-nutshell.com
https://physicsclassroom.com
A “structured self-study” education resource for learning university-level physics, reminiscent of the Physics Classroom HS-level site. Very sparse, well-thought-out writing with lots of illustrations, animations, and visualization, together with undergraduate-level math, as created and maintained by a professional web graphic designer, with intentional layout for mobile devices. I particularly enjoyed his calculus-based treatment of Earth's radiation energy balance and radiative forcing, which led me to his site.
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