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The dielectric constant measures how strongly the eletronic charge in the material can adjust to shield an external electric field, larger the dieletric constant, more effective is the screening. But for the electronic charge be able to adjust responding to the electric field, the electrons should be easily moved, which means that each electronic state will change assuming a polarized configuration. If the gap is large, the electric field can not mix the electronic states in the valence band with the electronic states in the conduction band, (think of perturbation theory, where the denominator will be of order of the band gap energy) so the electrons don't polarize much and the dielectric constant is small. On the other hand, in a metal, where the gap is zero, any small electric field mix the occupied states with the unoccupied ones, and we have a strong screening. The dielectric constant measures how strongly the eletronic charge in the material can adjust to shield an external electric field, larger the dieletric constant, more effective is the screening. But for the electronic charge be able to adjust responding to the electric field, the electrons should be easily moved, which means that each electronic state will change assuming a polarized configuration. If the gap is large, the electric field can not mix the electronic states in the valence band with the electronic states in the conduction band, (think of perturbation theory, where the denominator will be of order of the band gap energy) so the electrons don't polarize much and the dielectric constant is small. On the other hand, in a metal, where the gap is zero, any small electric field mix the occupied states with the unoccupied ones, and we have a strong screening.
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What is dielectric constant?
A dielectric is an insulating material that does not conduct electricity and is transparent to an electromagnetic field. Dielectric materials are used to separate conducting surfaces such as the plates inside a capacitor, wires inside transformers, electric cable conductors, and elsewhere in the electric industry where electrical separation of charged elements is necessary. The dielectric constant is a ratio of the capacitance of a capacitor in which a particular insulating material is the dielectric, to the capacitance of the capacitor in which a vacuum is the dielectric.
What is the difference between power semiconductors and semiconductors?
power semiconductorspower semiconductors can drive large currents during forward biassemiconductorsemiconductors drive small currents during forward bias
What statement best describes the design of the dumbbell buildings?
It was two large buildings connected by a narrow stairway
Statement best describes the design of the dumbbell building?
It was two large buildings connected by a narrow stairway
Why are dams built as part of large hydro power plants?
To gain a constant source of water.
Why do polar substance have a high dielectric constant?
Water, due to its polar nature, has a large dielectric constant. Therefore, water molecule has a very large electric dipole moment and is forced to rotate to respond to an alternate external electric field. Hence water as a liquid has a very large dielectric constant i.e. 80. Mica on the other hand is less polar as water and hence has low dielectric constant.
What is the relation between Dipole moment and Dielectric constant?
The dielectric constant is the ratio of the permittivity of a substance to the permittivity of free space. It is an expression of the extent to which a material concentrates electric flux, and is the electrical equivalent of relative magnetic permeability. As the dielectric constant increases, the electric flux density increases, if all other factors remain unchanged. This enables objects of a given size, such as sets of metal plates, to hold their electric charge for long periods of time, and/or to hold large quantities of charge. Materials with high dielectric constants are useful in the manufacture of high-value capacitors.
Why do sodium ions and chloride ions remain dissociated in the blood?
Blood has a sufficiently high proportion of water to have a large enough dielectric constant to promote the dissociation of the ions.
What is dielectric constant?
A dielectric is an insulating material that does not conduct electricity and is transparent to an electromagnetic field. Dielectric materials are used to separate conducting surfaces such as the plates inside a capacitor, wires inside transformers, electric cable conductors, and elsewhere in the electric industry where electrical separation of charged elements is necessary. The dielectric constant is a ratio of the capacitance of a capacitor in which a particular insulating material is the dielectric, to the capacitance of the capacitor in which a vacuum is the dielectric.
What is the difference between power semiconductors and semiconductors?
power semiconductorspower semiconductors can drive large currents during forward biassemiconductorsemiconductors drive small currents during forward bias
Why minority carriers in P-type is electrons?
The P-type semiconductors have a very large percentage of holes.
What is a narrow stripe of land that connects 2 large bodies of water?
A narrow stripe of land that connects 2 large bodies of water is an isthmus.
Difference between insulation resistance and dielectric strength?
INSULATION RESISTANCE: The insulation resistance is a measure of the capability of a material to withstand leakage of current under a Vdc potential gradient. DIELECTRIC STRENGTH: The dielectric strength is a measure of the ability of the material to withstand a large field strength without electrical breakdown, and is usually expressed in volts per mil (.001') or volts per cm of dielectric.
What oil is used in a Submersible pump?
It's a special dielectric oil. -Almost impossible to get unless in large quantities now.
What is a relevant constant?
true A 'constant' is a quantity that is fixed, relevant to whatever subject is being discussed. An example is the speed of light 'c' (186,200miles/sec.). What is still 'at large' is what it is constant 'with respect to' apart from both a dielectric medium (c/n), and 'all receivers', which is what is apparently found by all receivers in checking its frequency. Checking it's wavelength after interaction with a lens instead seems to provide a paradox free solution, but not yet resolvable with respect to current theory. There are many 'constants'
What a narrow channel connecting two large bodies of water?
it is a straight.
How come dragons have large butts?
They don't. They have rather narrow pelvis'
