Can G be determined by measuring heat transfer in a controlled environment?

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Discussion Overview

The discussion revolves around the feasibility of determining the gravitational constant G through heat transfer measurements in a controlled environment involving two known masses. Participants explore the relationship between gravitational force, friction, and heat generation.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant proposes that measuring heat generated by gravitational force between two masses could indicate the value of G, assuming all force is converted to heat.
  • Another participant argues that the gravitational force would not be sufficient to overcome static friction, thus no heat would be generated.
  • A participant questions whether the tendency of gravitational force to pull, even if it does not cause movement, could still channel energy into heat.
  • Further clarification is provided that force's tendency to change momentum does not equate to work being done if there is no displacement in the direction of the force.
  • One participant uses an analogy involving a rubber band to challenge the idea that force is only felt when movement occurs, suggesting that force is still experienced even without displacement.
  • Another participant emphasizes that for heat to be generated through friction, work must be done, which requires movement in the direction of the applied force.
  • A clarification is made that feeling a force does not imply that work is being done if there is no net movement.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between gravitational force, friction, and heat generation. There is no consensus on whether G can be determined through the proposed method, and the discussion remains unresolved.

Contextual Notes

Participants highlight assumptions regarding the conditions under which work is done and the role of displacement in energy transfer, which remain unresolved in the discussion.

rockyshephear
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Would it be possible to determine the value of G by setting two very well know masses side by side on a very well know surface of well known coefficient of friction, in a controlled environment, so that the force applied on the smaller by the larger would be transferred entirely into heat (minus any molecular rearrangements). And the amount of the heat change in the system could somehow indicate G?
 
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I don't think the gravitational force between the masses(even if huge) would overcome even static friction in the first place. So no question of heat generation either.
 
If there's a tendency for force to pull regardless if it can, does that create energy being channeled into heat?
 
rockyshephear said:
If there's a tendency for force to pull regardless if it can, does that create energy being channeled into heat?
Force's tendency is to change the momentum. That is what defines it. And if there is no component of displacement in the direction of force, it doesn't do work. Meaning, it doesn't change the energy of the body on which it acts. In this case there is no displacement at all.
 
So If I attach a thick tight rubber band around my body and a telephone pole, I'm not moving towards it so you're saying I don't feel any force? I only feel force when I give into the pull of the rubber band??
 
rockyshephear said:
So If I attach a thick tight rubber band around my body and a telephone pole, I'm not moving towards it so you're saying I don't feel any force? I only feel force when I give into the pull of the rubber band??

If you are not moving then you are not experiencing a net force. For heat to be dissipated via friction you must be doing work, hence a force applied over distance.
 
I said the force wouldn't be doing any work. Didn't say anything about what you 'feel'. You feel a force when the part of your body subject to the force tries to move while the remaining parts oppose it, whether the entire body gives in or not.
 

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