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AP®︎ Physics 2

An algebra-based, introductory college-level physics course that explores topics such as fluid statics and dynamics; thermodynamics with kinetic theory; PV diagrams and probability; electrostatics; electrical circuits with capacitors; magnetic fields; electromagnetism; physical and geometric optics; and a whole lot more.

AP®︎ Biology

Learn AP Biology using videos, articles, and AP-aligned multiple choice question practice. Review the fundamentals of biochemistry, cell biology, genetics, evolution, and ecology, and develop scientific thinking skills as you explore the study of life.

Cosmology and astronomy

It's a great, big universe out there. In this section of Khan Academy, you'll learn about the brain-bending vastness of time and space. We go from plate tectonics here on Earth to entire galaxies and beyond.

Health and medicine

The medical world can be a confusing place. Patients, their families, and even students entering health fields might feel overwhelmed by the large vocabularies and complicated explanations. We hope to make understanding the medical world a bit easier. Look around! These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay seeking it because of something you have read or seen in any Khan Academy video.

A brief introduction to biology

Biology, defined as the scientific study of life, is an incredibly broad and diverse field. In many ways, it's as kaleidoscopic and rich as living organisms themselves. Biologists study life at many scales, from cells to organisms to entire ecosystems. Begin your own biological journey here!
Start learning

A brief introduction to biology

Biology, defined as the scientific study of life, is an incredibly broad and diverse field. In many ways, it's as kaleidoscopic and rich as living organisms themselves. Biologists study life at many scales, from cells to organisms to entire ecosystems. Begin your own biological journey here!
Start learning

A brief introduction to physics

Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.
Start learning

A brief introduction to physics

Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.
Start learning

A brief introduction to chemistry

We will be covering the material in a first year introductory high school or college general chemistry course. This may be your first time taking chemistry, but chances are you know a lot of chemistry already from observing the world around you. We will learn how to explain phenomena by thinking in terms of the atoms that make up all matter, and how atoms interact. Basically, learning chemistry is like having telescopic vision!
Start learning

A brief introduction to chemistry

We will be covering the material in a first year introductory high school or college general chemistry course. This may be your first time taking chemistry, but chances are you know a lot of chemistry already from observing the world around you. We will learn how to explain phenomena by thinking in terms of the atoms that make up all matter, and how atoms interact. Basically, learning chemistry is like having telescopic vision!
Start learning