Jump to content

Pulvinar

Members
  • Posts

    4
  • Joined

  • Last visited

Everything posted by Pulvinar

  1. I can see why you're confused-- LZW bit strings are not text strings. They just happened to be using the upper-case alphabet in their example. In LZW the symbols could represent unique patterns of any data, such as an image, and the binary codes for the symbols will be as long as needed. What you're seeing with "OR" in the example is a new symbol being added to the dictionary that represents that pair of letters with a single symbol (whose bit pattern is just the next available code). It's the heart of the compression algorithm.
  2. Except that the plates could be made of different metals with different electron densities and be different thicknesses, so we can't just compare electron counts. But yes, the difference between the charges of the two plates determines the field strength. I don't really see the distinction there since the plates won't have a charge until it's created, but you've got the idea. Yes, that potential energy in the dielectric gets added -- it's part of the whole, just not a necessary part.
  3. Electric charge is an excess or a deficit of electrons relative to the number of protons in a material, not a slight displacement of them. Electrons need to be able to flow into or out of the material for it to have a charge, and that normally only happens with conductors, such as the plates. The slight displacement of electrons in a material dielectric requires a force (the electric field) and is a form of potential energy, but it's not a charge. The electric field is sustained by the charged plates (assuming no external circuit), and will be reduced by a material dielectric's slightly-displaced electrons.
  4. hoola, I think I see what's confusing you here: the energy in a capacitor is in the electric field created by the charge, not the charge itself. A dielectric is an insulator so no charge can flow in or out of it to build up. That includes a vacuum as a dielectric, which has the baseline permittivity (ε0, 8.85 pF/m). Material dielectrics are compared to ε0 for relative permittivity. In those, the electrons are slightly displaced by the field, thereby partially counteracting it and thus increasing the capacitance.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.