Is this sorta mechanical component ever made?

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Discussion Overview

The discussion revolves around the concept of deriving normal reactions from internal stresses in a body, particularly in the context of mechanical components and scenarios such as explosions in rigid containers. Participants explore whether such arrangements have been made and the implications of internal forces in these situations.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant proposes the idea of deriving normal reactions solely from stress within a body, using the example of an explosion in a rigid container to illustrate their point.
  • Another participant suggests that the original question may imply a misunderstanding of free body diagrams and internal forces, stating that internal forces cannot produce a continuous external effect.
  • Some participants clarify that spring compression and other forms of stress already provide normal reactions in conventional scenarios, questioning the need for a new arrangement.
  • There is a suggestion that the original poster may be seeking a form of reactionless propulsion or energy generation, which is met with skepticism regarding the feasibility of such concepts.
  • A later reply attempts to interpret the original question as seeking a net-unidirectional force through internal manipulation, indicating a more complex understanding of the mechanics involved.

Areas of Agreement / Disagreement

Participants express varying interpretations of the original question, with some agreeing on the conventional understanding of stress and normal reactions, while others remain uncertain about the intent and clarity of the inquiry. The discussion does not reach a consensus on the feasibility of the proposed concepts.

Contextual Notes

There are indications of missing assumptions and unclear definitions, particularly regarding the nature of internal forces and their implications in closed systems. The discussion reflects a range of interpretations without resolving these ambiguities.

dE_logics
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When a force falls on a body, it gets a normal reaction.

Conventionally this normal reaction can be given by friction, spring compression, chemical reaction, motion etc...

Now...have we ever made such an arrangement that this normal reaction is derived from the stress on a body...nothing else...or at at least some amount of normal reaction is derived from the stress in the body.

Just for examples sake...suppose a bomb explodes in a rigid container...all the the shock wave will be absorbed or normal reaction will be given back to that shock wave from the container's reaction to the stress made by the shockwave...or the strength of the container will give the normal reaction. In this case there's no net motion but there's a normal reaction cause of the rigid container (considering a perfectly homogeneous explosion, i.e shockwave completely distributed in space evenly).

If the explosion would not have been homogeneous, there would have been a net displacement, same for any force applying in one direction

What I am asking here is...has any arrangement been made so as to derive this normal reaction from the stress in the body even though the force is in one direction and without giving the total arrangement a net motion (small amount of motion is ok).

If you don't get it pls respond.
 
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I guess not.
 
You seem to be implying some sort of reactionless propulsion or energy generation. If so, you are misinterpreting the free body diagram of the forces. Internal forces will not ever sum to anything but zero externally on a continuous basis.
 
dE_logics said:
Conventionally this normal reaction can be given by friction, spring compression, chemical reaction, motion etc...

Now...have we ever made such an arrangement that this normal reaction is derived from the stress on a body...nothing else...or at at least some amount of normal reaction is derived from the stress in the body.
Emphasis Added

Spring compression is stress. When you place an object on a flat table the normal reaction is due to stress. This happens all the time.

However, if russ_watters is correct and you are asking about some sort of reactionless propulsion then you really misunderstand stress.
 
russ_watters said:
You seem to be implying some sort of reactionless propulsion or energy generation. If so, you are misinterpreting the free body diagram of the forces. Internal forces will not ever sum to anything but zero externally on a continuous basis.

When you shoot a bullet the force is internal.
 
DaleSpam said:
Emphasis Added

Spring compression is stress. When you place an object on a flat table the normal reaction is due to stress. This happens all the time.

However, if russ_watters is correct and you are asking about some sort of reactionless propulsion then you really misunderstand stress.

The reaction is to be derived from the internal stress of the body.
 
Do you mean like in a bouncing ball?
 
dE_logics said:
When you shoot a bullet the force is internal.

Yes. And the forces sum to zero in that case too (hence recoil).
 
Integral said:
Do you mean like in a bouncing ball?

No...like an explosion in a contained rigid chamber...the reason why its shockwave did not pass though the chamber is cause the normal reaction was given by the chamber.
 
  • #10
So are you just asking if anyone has ever made an explosion in a rigid chamber? If so, the answer is yes.
 
  • #11
:smile: :smile: :smile: :smile:

No man!...I used that to explain my point.
 
  • #12
OK, why don't you try a different explanation. I don't think anyone understands your question. A free-body diagram might help more than words.
 
  • #13
Agreed. We're only guessing at your point - you are being very vague.
 
  • #14
I believe the OP is attempting a net-unidirectional force through some type of exotic internal manipulation(explosive or otherwise)
In other words, a forced displacement of the center-of-mass and, more so, in a continuing, net-unidirectional force outcome within a closed-system.

That's a hard call...
 

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