Applying Newton's Second Law: Understanding Forces and Acceleration in a Galilean Reference Frame
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Newton's laws, Newton's second law, Galilean reference frame, first law of Newton, principle of inertia, external forces, mass, acceleration, weight, reaction force, force, inertia, Newton's three laws, classical mechanics, relativity, Galileo, Aristotle, rectilinear motion, uniform motion, special relativity, general relativity, Einstein, Newton's laws of motion, resultant force, vector addition, mass times acceleration, external forces summation, inertial reference frame, force exerted, Newton's third law, action and reaction, physics laws, mechanics principles, force and motion, inertia principle, Galilean invariance, Newton's law formulation, historical context of Newton's laws, application of Newton's second law, mathematical expression of Newton's laws, initial conditions, movement of objects, forces and motion, scientific theories evolution.
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Unlock the Secrets of Motion with Newton's Laws: Understand how objects move and respond to forces with our comprehensive guide. Discover the principles behind Newton's three laws, from the law of inertia to the relationship between force and acceleration. Learn how to apply these fundamental concepts to real-world problems, such as projectile motion and force interactions. Dive into the world of classical mechanics and explore the intricacies of motion, forces, and energy. Get instant access to in-depth explanations and examples that will help you grasp the underlying physics and make accurate predictions about the behavior of objects.
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[...] To properly apply Newton's second law, you must first choose a supposedly Galilean reference frame, that is to say where Newton's first law can be applied. List all the external forces that act on your object in this reference frame and finally write the formula of Newton's second law to deduce the value of the acceleration. If we take the example of an object that is subject only to its weight. This is what is commonly called free fall. Like, for example, a skydiver who jumps out of a plane. [...]
[...] But if he is still known nearly 300 years after his death and if he is still taught in school textbooks, it is mainly because he founded an entire branch of physics, the [...]
[...] We write Newton's second law, so the sum of external forces is equal to mass times acceleration. Here, the only external force is the weight. So we replace, we have the weight that is equal to mass times acceleration. Quick reminder, weight is equal to mass times the intensity of gravity g. We have m x g which is equal to m x a. We can simplify the two masses and we get that acceleration is equal to the intensity of gravity. [...]
[...] I risk disappointing you, but the first law of Newton is actually due to Galileo, even if other scholars, such as Descartes, also inspired Newton for the final writing. You see in the final formulation that we are talking about a Galilean reference frame. And indeed, the first law of Newton can only be applied if the reference frame is Galilean. But a Galilean reference frame, by definition, is a reference frame where the first law of Newton applies. We will explain what happens when we have this time forces that do not balance out. This is what Newton did with his second law. [...]
[...] He also says that the two forces will have the same value, the same direction, but opposite senses. To understand this formulation, let's say you're on a skating rink with a friend who is both of you are immobile. If you push your friend, you will exert a force on him and he will move in the direction of that force. What Newton's third law says is that your friend will ultimately also exert a force on you of the same value but opposite sense. [...]
