Aligning effect in uniform field

In summary: 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 directionThe component of velocity parallel to the force increases in magnitude. The component perpendicular to the force doesn't.
  • #1
reterty
29
2
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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  • #2
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.
 
  • #3
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
 
  • #4
For conservative fields, forces are typically related to the gradient of the potential vis. $$\vec E=-\nabla {\phi}$$ Is that what you need?
 
  • #5
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)
 
  • #6
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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  • #7
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
 
  • #8
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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FAQ: Aligning effect in uniform field

What is the aligning effect in a uniform field?

The aligning effect in a uniform field refers to the phenomenon where particles, molecules, or dipoles align themselves in a specific orientation when subjected to a uniform external field, such as an electric or magnetic field. This alignment minimizes the system's potential energy and can influence the material's overall properties.

How does the aligning effect occur in a uniform electric field?

In a uniform electric field, polar molecules or dipoles experience a torque that tends to align them with the direction of the field. The positive end of the dipole is attracted to the negative side of the field, and the negative end is attracted to the positive side, resulting in an alignment along the field lines.

What are some practical applications of the aligning effect in a uniform field?

The aligning effect has several practical applications, including the orientation of liquid crystals in display technology, the alignment of nanoparticles in materials science, and the manipulation of biological cells in biomedical engineering. It is also used in techniques like dielectrophoresis for particle separation and manipulation.

How does temperature affect the aligning effect in a uniform field?

Temperature can significantly impact the aligning effect. Higher temperatures increase the thermal motion of particles, which can counteract the aligning effect of the field, leading to a less ordered system. Conversely, lower temperatures reduce thermal motion, enhancing the alignment of particles in the direction of the field.

Can the aligning effect be observed in both electric and magnetic fields?

Yes, the aligning effect can be observed in both electric and magnetic fields. In an electric field, polar molecules or dipoles align with the field lines, while in a magnetic field, magnetic dipoles or domains align with the magnetic field lines. The underlying principle of energy minimization drives the alignment in both cases.

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