The behaviour of an uncharged dielectric particle in a capacitor

AI Thread Summary
An uncharged dielectric particle in a capacitor becomes polarized due to the electric field, but it does not acquire a net charge. The polarization leads to a surface charge distribution that can create a net force on the particle, especially when it is not centered between the capacitor plates. When the particle is closer to one plate, the resulting electric field and charge distributions indicate a net force acting on it towards the plate. Understanding these concepts can be enhanced through sketches of the charge distributions and electric field lines. For further study, resources on "Dielectric sphere in a uniform electric field" are recommended, as this is a common topic in electrostatics.
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Homework Statement
What happens to an uncharged particle with a dielectric constant (lower conductivity) when it is placed in a pair of parallel plate electrodes (charged)?
Relevant Equations
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I understand that the particle will be polarised according to its dielectric constant and the electric field across the capacitor.
However, since it is similar to an insulator and electrons do not move in and out of the particle easily, the particle will not be charged.
How then will polarisation cause the particle to move in a pair of parallel plate electrodes? Appreciate it if anyone could guide me/ direct me to any related books/ materials. I am a beginner in this topic, and have been looking through the internet but it's of little avail.
 
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Did you make some sketches of the field and charge distributions?

Let the particle be a sphere of dielectric material. You might start with a sketch where the particle is placed precisely halfway between the charged parallel plates. What does the surface polarization charge distribution look like on the sphere? What does the surface charge distribution look like on each plate? (It won't be uniform.) Roughly, what does the pattern of electric field lines look like? Is there a net force on the particle in this case?

Now suppose the particle is not halfway between the plates. For example, let the particle be placed very close to the positive plate. Sketch the charge distributions and field lines. Can you see that there will now be a net force on the particle? What is the direction of the net force?
 
If you google "Dielectric sphere in a uniform electric field" you will find quite a bit of information including videos. It is a standard problem in electrostatics and is a standard solved example in most intermediate level E&M textbooks as an application of the Uniqueness theorem to boundary value problems.

The question is, what is your level? If you don't quite understand what I'm talking about in the paragraph above, then @TSny's approach is the way to proceed. On the surface of the particle, draw teeny-tiny polarized football-shaped atoms with a ##+## and a ##-## at the two ends, all oriented in the same direction (which direction should this be?), then see what you can say about the net force on the particle.
 
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