The physics archive contains legacy physics content, and is not being updated with new content. For our most up-to-date, mastery-enabled courses, check out Middle School Physics, High School Physics, …

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Physics is built on a foundation of math and it seeks to explain all phenomena in the universe. It forms the basis for other sciences like chemistry and biology. Physics uses simple yet elegant math to …

Aug 18, 2025 · Explore Khan Academy’s updated AP Physics 1 and NGSS-aligned Middle School Physics courses, featuring new videos, interactive practice, and hands-on activities to support …

Let's solve some problems to better understand the behavior of forces that act on objects, and their effects on motion. In the process, we will clear some common misconceptions.

Unit 2: 4th quarter: Physics Unit mastery: 0% Evolving models of the universe Universal Laws of Physics: From Aristotle to Newton's Laws Light as a wave and a particle Understanding the Cosmos

Learn physics using videos, articles, and NGSS-aligned practice exercises. Explore the fundamentals of motion and forces, non-contact interactions, energy, and waves.

If you’ve mastered this content and want to explore physics at the next level, we recommend our AP Physics 1 and AP Physics 2 courses. Give us feedback on this course

This course has been deprecated. We recommend exploring our improved High School Physics, AP Physics 1, and AP Physics 2 courses instead.

In the physics sense, you are doing no work on the book. However, even if you don't have a book in your hand, if you twist side to side, your muscles get warm and you release energy.