Dielectric Charges: Explaining Why They Don't Attract

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Discussion Overview

The discussion revolves around the behavior of dielectric materials in the presence of electric fields, specifically addressing why dielectrics do not attract charges under certain conditions. It explores concepts related to polarization, induced charges, and the interaction of these factors with external electric fields.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes that dielectrics are typically neutrally charged polarizable materials that do not have a net charge, which explains their lack of attraction to charges.
  • Another participant argues that induced polarization in a dielectric can lead to attraction, citing the example of dust particles being attracted to a charged rod despite having no net charge.
  • A subsequent reply reiterates the point about induced polarization and its ability to create an electric field that can interact with other charges.
  • One participant expresses a desire to understand scenarios where charges would not attract, indicating a recognition of the complexity of the topic.

Areas of Agreement / Disagreement

Participants express differing views on the conditions under which dielectrics can attract charges, with some emphasizing the neutrality of dielectrics while others highlight the role of induced polarization. The discussion remains unresolved regarding the specific circumstances that may lead to attraction or lack thereof.

Contextual Notes

The discussion does not clarify the specific conditions under which dielectrics may or may not attract charges, leaving assumptions about uniform electric fields and the nature of induced charges unaddressed.

superslow991
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can someone in detail explain to me why can't a dielectric attract charges?
 
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Typically a dielectric is a neutrally charged polarizable material. When you apply an electric field, such as in a capacitor, the electric field will polarize it, inducing a smaller electric field in the opposite direction.

But yeah, the quick answer is that it doesn't have a net positive or negative charge.
 
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The induced polarisation in a dielectric can cause attraction. Dust particles are attracted to a charged rod even when they have no net charge.
So the OP is not strictly accurate except in a uniform field.
 
sophiecentaur said:
The induced polarisation in a dielectric can cause attraction. Dust particles are attracted to a charged rod even when they have no net charge.
So the OP is not strictly accurate except in a uniform field.

This is also true. Any induced charge will create it's own electric field as I said, which can interact with charges the way any other electric field would.
 
TJGilb said:
This is also true. Any induced charge will create it's own electric field as I said, which can interact with charges the way any other electric field would.
I know that they can attract but just wanted to know in an instance where charges wouldn't attract. Thanks for the replys
 
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