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  • electrostatics - Why is capacitance increased with a dielectric rather . . .
    A dielectric with high permittivity $\varepsilon$ permits (requires) more polarization for a given field magnitude than a low permittivity one More polarization means more charge stored, so the high $\varepsilon$ material must hold more charge for a given field to be measured across it when used as a dielectric in a capacitor
  • Why is the dielectric strength decreasing with thickness
    I wonder why the dielectric strength is higher the thinner the material is: quot;Dielectric films tend to exhibit greater dielectric strength than thicker samples of the same material quot; Sou
  • condensed matter - What is the mechanism of dielectric saturation . . .
    The dielectric is a very polar, protic solvent, presumably water (few other solvents dissolve ions, polar aprotic almost never, exept ion pairs, but this is a different story) The dielectric constant (DC) of protic solvents is "produced" by orientation polarisation, this is reason for the DCs being very high compared to nonpolar substances
  • Displacement current in a dielectric - Physics Stack Exchange
    Further, this would imply that the equation for net displacement current in a dielectric medium would be $\epsilon_ok \frac {d\phi_E} {dt}$ However, this result doesn't make intuitive sense to me Could someone please explain if there's a problem with my thinking here?
  • What is the difference between a dielectric and a semiconductor?
    A dielectric is always an insulator A semiconductor can be an insulator or a conductor depending on conditions such as whether an electric field is present For example a transistor can be used as a switch by applying a voltage across it or not If the voltage is on it allows current to flow and if the voltage is off it doesn’t
  • Dielectric constant of water - Physics Stack Exchange
    A relative dielectric constant at $100$ Hz of about $4000$ So, I cannot interpolate back in frequency (I put a link to the paper at the end) Does anyone have any info about where I could find this data? I know that for constant current and about $20$ C the constant is $80 1$ What about at $50$ Hz?
  • Is free space a dielectric? - Physics Stack Exchange
    The physical constant $\\epsilon_0$ is usually called quot;permittivity of free space quot; or quot;vacuum permittivity quot; Griffiths says: I dislike the term, for it suggests that the vacuum is
  • electricity - Why do we use dielectric materials in a capacitor . . .
    Dielectric materials tend to be more insulating than air, and thus by using such a material the plates (in a parallel plate capacitor) can be placed closer together which would yield higher capacitance Capacitors with air in between them do exist


















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