How Fast Do Mechanical Forces Travel Through Different Mediums?

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Discussion Overview

The discussion revolves around the speed at which mechanical forces travel through different mediums, particularly in the context of pulling a rope and the implications of force transmission in various materials. Participants explore theoretical models, real-world limitations, and the relationship between mechanical forces and concepts from relativity and string theory.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions the time it takes for a force to travel through a rope when pulled, suggesting it relates to the speed of wave propagation.
  • Another participant explains that in ideal models, the speed of force is considered infinite, but in reality, it is limited by the atomic structure's ability to adapt, specifically referencing the speed of sound in materials.
  • A third participant notes that relativity prohibits the existence of rigid objects, which aligns with the initial query about inextensible ropes.
  • One participant proposes that if gravity is related to string mechanics, it could imply an infinite speed of force, but if gravity has a finite speed, it raises questions about the nature of gravitational transmission and the existence of massless particles like gravitons.
  • Another participant introduces the concept of instantaneous effects observed in quark pairs and theorizes about potential macro-level applications, such as using the Kazimir effect to create communication models that operate faster than light.

Areas of Agreement / Disagreement

Participants express differing views on the nature of force transmission, the implications of relativity, and the relationship between gravity and mechanical forces. No consensus is reached on these topics.

Contextual Notes

Participants acknowledge limitations in their models, such as the assumptions of ideal conditions versus real-world physics, and the unresolved implications of force transmission speeds in relation to relativistic effects.

jay
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Hai friends..
We are getting enough data on speed of gravity.But what about
the speed of other mechanical forces.
When I am pulling one side of a long rop how much time will
it take to reach the othe side .I don't know, may be the speed of wave.
I think if I pulls an inextensible light weight rope
i can move it towards me without a time waste.Then that makes problems.If I tied one side of the rop to a massive object like sun and started pulling indeed i can pull it without any difficulty atleast for 8 minutes.If I am pulling with half the speed of light
it will be get extended to millions of km.So what is the solution to this.
 
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When you work with ideal models - inextensible cords, perfectly elastic billiard balls and all - you pretty much assume the "speed of force" is infinite. But in the real world force can't be transmitted any faster than the atomic structures can adapt to it. If you push on a metal rod, the force is transmitted to the other end by the adaptations of the rod's electronic structures. And than can't go any faster than the speed of sound in that metal.
 
In relativity there cannot be any rigid objects (or "inextensible rope") for exactly the reasons you give.
 
Isn't it C?

I thought a photon exerts a force, so wouldn't it be C?

Anyway, I just spotted a post about data on the speed of gravity, which is something I'm interested in because of its relevance to string theory models, and I'm new to these boards, so this might be a naive observation: If gravity is an artifact of "string" mechanics, then it is "inextensible rope" and the speed of force is infinite; however, if gravity has a speed, such as light seems to, this would cause serious problems in the model of the universe now because it would imply that gravity is transmitted by something that has mass: e.g., the Graviton.

There is one good argument for the concept that gravity is rigid, and that's by examining quark pairs whereby you can separate the pairs, affect one, and produce instantaneous effect on its counterpart -- even faster than C. The concept exists in physics. It has also been theorized that this effect can be produced on a macro level by utilizing the Kazimir effect to "pair" large superconducting plates in vacuum and then physically separating the plates, thereby producing a working model for the trekkie "subspace communicator."
 

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