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Nedcim

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About Nedcim

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  1. I have previously appealed to this forum's moderating staff who were involved in a thread which was closed, citing that I was not arguing in good faith. Nothing could further from the truth. I'm going to prove that the moderating staff willfully ignored accepted science in favor of staff opinion. This was the moderator's claim: "If equilibrium exists, is a matter of the second law. Not the third." This claim was the basis of repeated variations used in a discussion against me. The claim fails. Newton's Third Law is fundamental to static equilibrium. Here are two e
  2. It's obviously implied. There are no force arrows depicting forces exerted by the book. Yet somehow you were able to made this claim: You have contradicted your argument. Nonsense. The normal forces are third law pair they can't act on the same object. How convient? I kept repeating that argument yet somehow I missed every single reply which confirmed it. That seems suspect just like one of my replies which was butchered even though it was copied and pasted from wordpad with no error. Comparing conditions of objects that are in stat
  3. You are entirely wrong. You have repeatedly failed to acknowledge that a normal force from the derrick must be countering the normal force from the rock. A reaction is exerted by the object. Are you denying that the derrick is exerting a normal force on the rock? More strawman from you. I said nongravitational forces result in action/reaction pair. That's exactly what I said early in this thread: You, nor anyone else acknowledged that the normal forces from the desk and book constituted a third law pair until I cited several sources which explictly made
  4. You quoted me, yet my quote says nothing about a normal force countering gravity. In any case, the diagram from the physics book said: "The normal force of the rock counters gravity." Are you saying that the book is wrong? The nongravitational forces result in an action/reaction pair. Early in this thread, I mentioned about the desk pushes the book; book pushes the desk. I noted about the opposing normal forces from the desk and book. I talked about the results of gravity i.e. the normal forces etc. You, nor anyone else acknowledged that those were third law pai
  5. All objects with mass exert an attractive force on one another by universal gravition. However, the force that the book exerts on Earth is negligible. I have never insisted that the normal force be paired with gravity that was done by you. What I've said is that the force of gravity on an object results in an external force. It's the external force that is countered by a nongravitational force. My inconsistency? I suppose you're going to ignore the BBC Corp., Encyclopedia Britannica, Yale University etc. They all published material that ignores the strict considerations and simply label
  6. The subject is identical. The only change is that it ignores that interaction from Earth which is trvial for the vast majority of applications. Instead it focuses on the objects in contact, and simply labels that interaction as a third law pair. You won't acknowledge that a force must be countering the normal force from the rock from derrick example. More excuses. I haven't. You made the decision to resort strawman to avoid the consequences of accepting BBC article which went against your claim. What is unique is that the desk/book interaction is not an action/rea
  7. The derrick is composed of many objects. I can't help if you choose to ignore simplest case of two books stacked together because it goes against your claim. You failed to acknowledge that some force must be countering the normal force from the rock. Those two forces satisfy the given criteria. Sure, ignore the simple case because it refutes your claim. Only in the strictest case. Refer to vollyball diagram. Same direction for identical forces? That's not true: https://www.chegg.com/homework-help/questions-and-answers/three-cases-
  8. No, an object can be composed of other objects. Stack up two books and now two objects have combined to form one object with no net force acting them. No reaction forces? It explictly notes that the normal force of the rock counters gravity. What is countering the normal from the rock? The normal force from the base of the derrick. They must form an action/reaction pair. The book and desk are in equilibrium, solely by opposed normal forces. Your mistake. You mentioned that Newton's third law does not apply. Then noted that they don't have to be equal etc. Those
  9. There is no consideration of the forces acting on the ball and bat only their resulting opposed normal forces. While the desk and book considers the forces that result in the opposed normal forces. That's not true at all. Again, refer back to the derrick example. It's comprised of many objects yet the derrick itself has no net force because of its suitable reactions. The deformation forces will definitely negate gravity. Take a piece of clay and press it against a wall, it not resist gravity until sufficient deformation. Then what what was you referring to wit
  10. The ball changes direction. There must be an instant when the force from the bat is equal but opposite the force of the ball, for that time there is no net force in the horizontal direction. Both the ball and bat will deform, negating the net force of gravity. External force of zero gives equilibrium. How can the forces be third law pair but not be equal magnitude or opposite in direction? That gives a contradiction. The same acting forces on two examples but with different results. There is must be more consideration other than two forces acting on the same object.
  11. No, the example explictly said that the forces were not an action/reaction pair. The reason given here was two forces acting on the same object. That's the case with a ball hit by a bat so it should fail to be a third law pair by the same convention. Exactly, no condition of time. Hence, static equilibrium could be for an instant. Third law can be applied to forces that are not an action/reaction pair? How are you going to eliminate an external force or torque without an action/reaction pair? All of the forces act on the object. Notice how all of those forces hav
  12. Again, equilibrium doesn't matter with the bat and ball only the two forces acting on the ball. The book and desk were in equilibrium but forces on the book were not an action/reaction pair. How can Newton's third law be applied to forces that are not an action/reaction pair? There is no condition of time for equilibrium. That dilemma is going to be present with innumerable examples where the force of gravity and another force act on an object. Sure, they will. Refer back to the static equilibrium -derrick example. Explain why that example is wro
  13. It is irrelevant to consider the magnitudes of forces acting on different objects. True, because they involve two different examples. I didn't intend for the examples to be directly related. In any case, you completely ignored the cited material from the website which disagreed with your claim about equilibrium having no connection with action reaction pair. Why? I never insisted on equilibrium for the bat and ball. In any case, they are in equilibrium for an instant but that is unimportant. What matters is that is that there are two forces acting on the ball when it colli
  14. Fair enough. It's used to show the justification for how the forces are assumed between objects for equilibrium contrasted with different types of forces but it's from a PDF file. Here's a a webpage that gives the same connection with Newton's third law and equilibruim: If someone hits a ball with a bat the ball is sent flying in the opposite direction. This is a result of Newton's third law. However, at the instant of contact there are two forces acting on the ball. The normal force from the bat and force of gravity. No different than case with the book on the table which had the n
  15. Obviously not when offset is being applied to the forces between objects that are in direct contact. Equilibrium depends on the consequences of Newton's third law. You've already seen a few examples. Here Newton's third law is explictly given in the intro to statics:
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