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Currently Playing: The One Principle That Explains All Physics - But Why?

Thanks to Brilliant for sponsoring this video! Try everything Brilliant has to offer at https://brilliant.org/PhysicsExplained — and get 20% off an annual premium subscription. The Action Principle lies at the heart of modern physics, from mechanics to electromagnetism, relativity, and the Standard Model. In this video, we explore why a simple thrown ball follows one particular path out of infinitely many, and how this reveals a deeper rule: the physical path is the one that makes the action stationary. Using clear visuals, we build the action from kinetic and potential energy, see how small variations lead directly to the Euler–Lagrange equation, and recover Newton’s Second Law as a natural consequence. This principle, expressed through the Lagrangian, becomes the unifying framework behind the laws of motion throughout physics. 🤝 Support the channel Patreon → https://www.patreon.com/physicsexplained 🔗 Follow me Instagram → https://www.instagram.com/physics_explained_ig X (Twitter) → https://twitter.com/PhysicsExplain1