Aligning effect in uniform field

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SUMMARY

The discussion centers on the aligning effect of particles in a uniform potential field, where the directions of instantaneous velocity and field strength converge over time. The participants explore the Maximum Power Principle as a potential explanation for this phenomenon, suggesting that systems tend to maximize energy transfer from potential to kinetic forms. The conversation emphasizes the role of conservative fields, specifically gravitational and electric fields, and the relationship between force and the gradient of potential. The stationary-action principle is highlighted as a method to demonstrate the alignment of velocity and force vectors.

PREREQUISITES
  • Understanding of classical mechanics, particularly kinematics and dynamics.
  • Familiarity with the Maximum Power Principle and its implications.
  • Knowledge of conservative fields and their mathematical representation, specifically the gradient of potential.
  • Comprehension of the stationary-action principle in physics.
NEXT STEPS
  • Study the Maximum Power Principle in detail and its applications in physics.
  • Explore the mathematical formulation of conservative fields, focusing on the equation $$\vec E=-\nabla {\phi}$$.
  • Investigate the stationary-action principle and its role in classical mechanics.
  • Examine specific examples of particle behavior in uniform potential fields to illustrate the aligning effect.
USEFUL FOR

Physicists, students of classical mechanics, and researchers interested in the dynamics of particles in potential fields will benefit from this discussion.

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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