What is Dielectrics: Definition and 154 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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    Parallel Plate Capacitor and Dielectrics

    I have a lab to do tomorrow with this topic. Just wondering if anyone can tell me a brief summary of what this is about and what I should be looking to accomplish/learn
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    How Does Gauss's Law Change in Dielectric Materials?

    Hey everyone, this is my first question on here, but I've seen you all be very helpful to others to I was hoping someone could clarify something for me. 1. How does Gauss law modify in dielectric materials?
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    How Does Changing Plate Separation Affect Energy Stored in a Capacitor?

    I need some help with these problems: 1) A parallel-plate vacuum capacitor has 7.36 J of energy stored in it. The separation between the plates is 3.64 mm. If the separation is decreased to 1.40 mm, what is the energy stored if the following events occur? a) the capacitor is disconnected from...
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    Capacitors with dielectrics

    I am supposed to design an energy storage system for a car, so I want to calculate how much energy can be stored in a capacitor whose geometry matches the car. As a baseline, we have an area 150 cm wide by 2500 cm long by 30 cm tall. The capacitor is a sandwich geometry , one layer of...
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