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avast2
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Does anyone has any documents to prove (law of lever)? Thank you!
Discover the Law of Levers: Uncovering Evidence and Documents | Prove It Now!
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In summary, the law of lever can be proved using the principle of virtual work, which states that in equilibrium, the virtual work done by external forces is equal to the virtual work done by internal forces. This can be applied to situations involving levers to determine the equilibrium condition.
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berkeman
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Can you give some links to the reading you've been doing on this question? What have you found so far? Can you state the "Law of Levers" that you are referring to?
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wrobel
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the angular momentum theorem is proved in textbooks. "law of lever" is a particular case
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sophiecentaur
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There are far fewer keystrokes involved in clicking on Google than in composing a question on PF. I hope you did that first.avast2 said:
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avast2
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berkeman said:
I searched some proof online but actually I want to find the proof of the kind of lever (such as Hammers pull the nails)
Thanh you!
I attach pictures ( - the proof that I had ; the kind of lever that I want to search the proof)
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avast2
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wrobel said:
Thanks, I will search the book,
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sophiecentaur
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What you are showing is not an actual 'proof'. It is an example of where that 'law' applies. The 'Principle of Moments' can be applied (look it up) to situations where there is a fulcrum (pivot) that can be identified and where two or more forces in equilibrium and where they are acting can be identified. See-saws are the easiest examples but the principle can also be applied to a hammer and other wrenches when the geometry of the two forces is not so obvious.avast2 said:
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Lnewqban
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russ_watters
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What exactly do you mean by "proof" or "prove" in this context? In physics, you prove theories/laws with experiments, but people tend not to use the word "prove" much. Do you mean a mathematical proof or derivation?avast2 said:
It's an odd question, which is why you aren't getting much help. Explaining your issue in detail may help us help you.
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Perhaps he means the "proof" of the laws of levers? It's just the equilibrium condition that the net troque must be 0. Take this figure from the corresponding Wikipedia article:
https://en.wikipedia.org/wiki/Lever#/media/File:Lever_Principle_3D.png
You take of course the gray point as the reference point here. Obviously the total torque here is
$$\tau=M_1 a-M_2 b$$
counting the component positive when pointing out of the paper. Thus the equilibrium condition ##\tau=0## tells you that ##M_1 a=M_2 b##.
https://en.wikipedia.org/wiki/Lever#/media/File:Lever_Principle_3D.png
You take of course the gray point as the reference point here. Obviously the total torque here is
$$\tau=M_1 a-M_2 b$$
counting the component positive when pointing out of the paper. Thus the equilibrium condition ##\tau=0## tells you that ##M_1 a=M_2 b##.
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nucl34rgg
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You may find it helpful to read about the principle of virtual work.
https://en.wikipedia.org/wiki/Virtu...ibrium the,the reaction, or constraint forces.
The law of lever can be proved using this.
https://en.wikipedia.org/wiki/Virtu...ibrium the,the reaction, or constraint forces.
The law of lever can be proved using this.
FAQ: Discover the Law of Levers: Uncovering Evidence and Documents | Prove It Now!
1. What is the law of levers?
The law of levers is a fundamental principle in physics that states that the force applied to a lever is directly proportional to its distance from the fulcrum. In simpler terms, it means that the longer the lever, the less force is required to move an object.
2. How is the law of levers used in everyday life?
The law of levers is used in a variety of everyday objects, such as seesaws, scissors, and wheelbarrows. It is also used in more complex machines, like cranes and forklifts, to lift heavy objects with minimal effort.
3. What evidence and documents can be used to prove the law of levers?
There are several historical documents and scientific experiments that can be used to prove the law of levers. These include Archimedes' Principle, which describes the relationship between the weight of an object and the amount of water it displaces, and Galileo's experiments with inclined planes.
4. How does the law of levers relate to other laws of physics?
The law of levers is closely related to other laws of physics, such as the law of inertia and the law of action and reaction. These laws work together to explain the movement and balance of objects in the physical world.
5. Why is it important to understand the law of levers?
Understanding the law of levers is important because it is a fundamental principle in physics and is used in many practical applications. It also helps us understand the mechanics of how objects move and the relationship between force and distance.