Why Newton's 3rd Law is Conservation of Momentum in Disguise

Physics with Elliot December 9, 2021
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Physics with Elliot

@physicswithelliot

About

I’m Dr. Elliot Schneider and I want to help you learn physics! Whether you’re a beginner just starting out with your physics studies, a more advanced student, or a lifelong learner, I hope you’ll find resources here that enable you to deepen your understanding of the laws of nature. Sign up for my newsletter and get the notes for my videos: https://courses.physicswithelliot.com/notes-sign-up If you find the content I’m creating valuable and would like to help make it possible for me to continue sharing more, please consider supporting me if you’re financially able. You can set up a monthly contribution at Patreon.com/PhysicsWithElliot, or make a one-time contribution at PhysicsWithElliot.com/support-me. Me: Elliot Schneider PhD, Physics, Harvard University BS, Physics, California Institute of Technology [email protected] PhysicsWithElliot.com

Video Description

Newton's third law says that for every action there's an equal-but-opposite reaction. Hidden inside it is a deep principle of physics: conservation of momentum! Get the notes for free here: https://courses.physicswithelliot.com/notes-sign-up Newton's third law looks a little strange the first time you see it: all forces between particles come in equal-but-opposite pairs. But it's really all about a more intuitive physical principle: the conservation of momentum. It implies that in an isolated system---meaning one where there are no outside forces acting on it---the total momentum will be conserved. I'll explain why in this video. But there's a catch: Newton's third law isn't always true! Get the links here: https://www.physicswithelliot.com/third-law-help-room A more advanced video about Noether's theorem: https://youtu.be/O0NYaO_OnH4 Tutoring inquiries: https://www.physicswithelliot.com/tutoring If you find the content I’m creating valuable and would like to help make it possible for me to continue sharing more, please consider supporting me! You can make a recurring contribution at https://www.Patreon.com/PhysicsWithElliot, or make a one time contribution at https://www.physicswithelliot.com/support-me. Thank you so much! About physics help room videos: These are intro-level physics videos aimed at students taking their first physics classes. In each video, I'll teach you the fundamentals of a particular physics topic you're likely to meet in your first classes on mechanics and electromagnetism. About me: I’m Dr. Elliot Schneider. I love physics, and I want to help others learn (and learn to love) physics, too. Whether you’re a beginner just starting out with your physics studies, a more advanced student, or a lifelong learner, I hope you’ll find resources here that enable you to deepen your understanding of the laws of nature. For more cool physics stuff, visit me at https://www.physicswithelliot.com.

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