Ending Strange Arguments: Simple Tips for Maintaining Peace

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Discussion Overview

The discussion revolves around a visual problem involving equilibrium and the center of mass of an object with an extension. Participants are trying to clarify the concepts of equilibrium, moments, and the behavior of the center of mass in different configurations.

Discussion Character

  • Debate/contested, Conceptual clarification, Exploratory

Main Points Raised

  • Some participants express confusion about the visual representation, questioning the identities of the red and blue objects and the pivot point.
  • One participant argues that if the first image represents equilibrium, then the second image cannot also represent equilibrium based on the distances to the center of gravity.
  • Another participant suggests that the object in question is akin to a hatchback with the trunk open or shut, indicating that the center of mass does not move despite changes in shape.
  • A participant challenges the claim that the center of mass does not move, asserting that it does move, which leads to further discussion about the nature of that movement.
  • There is a reference to a video that may provide additional context or clarification regarding the discussion, with some participants expressing enjoyment of the video.
  • One participant expresses doubt about the correctness of a previous statement, indicating that there may be inaccuracies in the claims made.

Areas of Agreement / Disagreement

Participants generally do not agree on the interpretations of the visual problem and the implications for equilibrium and center of mass. Multiple competing views remain, and the discussion is unresolved.

Contextual Notes

There are unresolved assumptions regarding the definitions of equilibrium and the specific configurations of the objects discussed. The mathematical reasoning presented relies on the interpretation of the visual elements, which some participants find unclear.

Lord Ping
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I can't put it more simply than this:

35672591.jpg


Please end this strange argument before I go mad over it.
 
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Well, this doesn't make much sense to me. What's the red thing? What's the blue thing? What's the pivot? It looks to me like a blue brick sitting on a table. I don't get it.

- Warren
 
Hi everyone,

If the first is equilibrium then the second is not.

In the first picture the centre of the gravity of the blue object is on the right of the pivot, let’s say that the distance between the pivot and the centre of the gravity of the blue object is D.

Similar the distance between the pivot and the centre of the gravity of the red object is d then if we want to have equilibrium the moments of the two object must be equal so we have: md=MD (1) (M: the mass of the blue object and m: the mass of the red object).

With similar thoughts in the second picture (we have supposed that there is equilibrium in the 2nd picture) you end up to the equation md’=MD (2) (d’: is the new distance between the pivot and the centre of the gravity of the red object).

If we had equilibrium in the 2nd picture then from (1) and (2) we have: d=d’ which is atop. So in the 2nd picture we do not have equilibrium.
 
Originally posted by chroot
Well, this doesn't make much sense to me. What's the red thing? What's the blue thing? What's the pivot? It looks to me like a blue brick sitting on a table. I don't get it.

- Warren

It's an object with an extension stuck on to it. Like, for instance, a hatchback with the trunk (or boot) open/shut. It's on a balance.

The centre of mass of the single blue+red object doesn't move, but the object does change shape - the red section moves. The question is will this change the moment?

Seemingly yes.
 
Originally posted by Lord Ping
The centre of mass of the single blue+red object doesn't move
Bull**** -- of course it does.

- Warren
 
It moves down slightly, but that doesn't matter... does it move horizontally too?
 
Of course.

- Warren
 
Pehaps the ending of this little video is what this is all about.
 
I love that video!
 
  • #10
i don't think that is compleatly correct
 

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