Aligning effect in uniform field

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Discussion Overview

The discussion revolves around the nature of an aligning effect observed in a uniform potential field, specifically how the directions of instantaneous velocity and field strength converge over time. Participants explore theoretical principles that might explain this phenomenon, including the least action and maximum power principles, while also considering specific examples and the role of forces in conservative fields.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that the aligning effect may be related to a general principle, possibly the maximum power principle, which posits that systems tend to maximize energy transfer from potential to kinetic forms.
  • Another participant emphasizes the need for a specific example to clarify the discussion, noting that the interaction between particles and the fluid is orientation dependent, with some orientations being more stable.
  • There is a mention of classical gravitational or electric fields as examples of force fields relevant to the discussion.
  • A participant points out that in conservative fields, forces are related to the gradient of the potential, referencing the equation $$\vec E=-\nabla {\phi}$$.
  • Another participant expresses confusion regarding the nature of the aligning effect, suggesting that the aligning agent is simply a force.
  • One participant proposes that using the stationary-action principle could demonstrate that the vectors of instantaneous velocity and force should align over time.
  • It is noted that the component of velocity parallel to the force increases in magnitude, while the component perpendicular to the force remains unchanged.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the nature of the aligning effect, with multiple competing views and interpretations of the principles involved. Some participants seek clarification and specific examples, while others propose theoretical frameworks.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the nature of forces and fields, as well as the dependence on specific examples to illustrate the aligning effect. The mathematical steps and definitions involved in the principles mentioned remain unresolved.

reterty
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I would like to discuss the nature of the following effect. At whatever angle and with whatever initial speed the particle fly into a uniform potential field, over time the directions of the instantaneous velocity and field strength converge. The kinematics and dynamics here are trivial, but I wondered: is there any general principle (such as the least action) that dictates this effect? Long attempts led me to a very vague "Maximum power principle" https://en.wikipedia.org/wiki/Maxim...T.,that reinforce production and efficiency." which in relation to this problem can be formulated as follows: "the system tends to move to such a movement that the power transfer of energy from potential to kinetic was maximum. It seems to be true, since instantaneous power is defined as the scalar product of force and instantaneous speed...
 
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I think you need a specific example to reduce the field of discussion.

The interaction between the particles and the fluid will be orientation dependent. Some orientations will be stable, and so remain for longer, increasing membership of that orientation population.
 
Baluncore said:
I think you need a specific example to reduce the field of discussion.

The interaction between the particles and the fluid will be orientation dependent. Some orientations will be stable, and so remain for longer, increasing membership of that orientation population.
I mean force fields: classical gravitational or electric field
 
For conservative fields, forces are typically related to the gradient of the potential vis. $$\vec E=-\nabla {\phi}$$ Is that what you need?
 
hutchphd said:
For conservative fields, forces are typically related to the gradient of the potential vis. $$\vec E=-\nabla {\phi}$$ Is that what you need?
No, my question concerns the nature of the aligning effect (see above)
 
In my vernacular the aligning agent is called a force. So I am completely clueless as to what you are asking..
 
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hutchphd said:
In my vernacular the aligning agent is called a force. So I am completely clueless as to what you are asking..
Ok, it is necessary using the stationary-action principle show that the vectors of the instantaneous velocity and force over time should approach each other in direction
 
The component of velocity parallel to the force increases in magnitude. The component perpendicular to the force doesn't. What else would be needed?
 
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