What is Dielectric: Definition and 730 Discussions

In electromagnetism, a dielectric (or dielectric material) is an electrical insulator that can be polarized by an applied electric field. When a dielectric material is placed in an electric field, electric charges do not flow through the material as they do in an electrical conductor, but instead only slightly shift from their average equilibrium positions, causing dielectric polarization. Because of dielectric polarization, positive charges are displaced in the direction of the field and negative charges shift in the direction opposite to the field (for example, if the field is moving parallel to the positive x axis, the negative charges will shift in the negative x direction). This creates an internal electric field that reduces the overall field within the dielectric itself. If a dielectric is composed of weakly bonded molecules, those molecules not only become polarized, but also reorient so that their symmetry axes align to the field.The study of dielectric properties concerns storage and dissipation of electric and magnetic energy in materials. Dielectrics are important for explaining various phenomena in electronics, optics, solid-state physics, and cell biophysics.

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  1. CassieFordham

    Layering different dielectric materials to increase breakdown voltage

    This is a general question, not a homework question, and @berkeman said I should post it in the EE forum... I'm trying to get a better understanding of the relationship of dielectric constant (relative permitivity) to dielectric strength (breakdown voltage).I want to know what happens when you...
  2. Phylosopher

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  3. J

    How Does Melting Affect the Polarizability and Dielectric Constant of a Medium?

    I understand that as a solid melts, it increases can increase in polarizability of the medium, and increase the Dielectric constant (K). -ex. like dissolving NaCl and having ions in solution. Why does Thermal motion reduce the polarizability of the medium, thus decreasing the dielectric...
  4. Kangaroos

    Dielectric in a uniform external field

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  5. E

    Dielectric slab and angle of incidence

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  6. L

    Dielectric strength and breakdown voltage capacitor

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  7. lonewolf219

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  8. T

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  9. 1

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  10. 1

    I need to make or buy a insulated wire Mesh

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  11. person_random_normal

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  12. Carlos de Meo

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  13. psuedoben

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  14. Dystopian

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  15. S

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  16. O

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  17. A

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  18. RoboNerd

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  19. C

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  20. K

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  21. S

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  22. bananabandana

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  23. I

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  24. V

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  25. I

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  26. I

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  27. S

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  28. S

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  29. K

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  31. H

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  32. A

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  33. E

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  34. JordanHood

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  35. mattbeatlefreak

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  36. gracy

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  37. E

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  38. P

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  39. B

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  40. emeriska

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  41. J

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  42. T

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  43. K

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  44. K

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  45. A

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  46. E

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  47. gracy

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  48. gracy

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  49. Titan97

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  50. Titan97

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