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- What is Newton's 3rd Law?
What is Newton's 3rd Law?


Let’s say we have block 1 that’s heading towards a stationary block 2. When they collide, block 1 exerts a force against block 2 (F_12) and block 2 exerts the same force back against block 1 but in the opposite direction (F_21), causing both blocks to accelerate in opposite directions.
This collision is an example of Newton’s 3rd Law in action: exerting a force against one object causes the object to exert the same force back in the opposite direction.
It seems weird at first because you think: ‘why doesn’t opening a door cause me to move backwards’? Instead, opening a door induces a small strain on your hand as a consequence of this law.
This topic, along with several more from forces, torque, and energy will be featured in Version 2 of my ‘Physics as a Science’ guide dropping tomorrow (read below for more)!
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Dropping Tomorrow: Physics as a Science (Version 2)!

The reason why you struggle in physics is because you don’t understand the science. You could easily compute basic equations like F=ma or W=Fdcos(θ) but if you run into a new problem you haven’t seen before, you’re screwed.
That’s why I’m releasing version 2 of my physics guide focusing on teaching you how to understand physics intuitively as a science tomorrow so that you’ll never have to memorize a practice problem again since you understand the science very well.
Version 2 will feature every topic from version 1 (motion) along with over 600 pages of new topics including Newton’s laws, forces, center of mass, torque, and energy introduced in such a way that you could’ve derived these equations yourself. Down below are some of the slides featured in Version 2!
Make you purchase the guide tomorrow on Monday, May 18th!
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Since you’re Here, check out my other offers to succeed in STEM!

The hardest part about math isn’t the raw calculations: it’s understanding what the math means when rearranging and graphing functions. Most students aren’t trained to interpret the math from a qualitative perspective which is why many students who are ‘good at math’ struggle in introductory chemistry, physics, and engineering courses.
That’s why I’ve created the Ultimate Algebra Guide for Science & Engineering Majors which covers all of the relevant concepts from algebra, trigonometry, and precalculus courses that are applicable for science & engineering majors condensed into a 700+ page guide!
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