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Why does coulomb force between two point charges depends upon dielectric constant of the intervening medium?
Wiki User
∙ 15y ago
It is because when a dielectric is placed between the charges , the dielectric gets polarized and the net electric field between the two charges decreases, hence force = charge x electric field also decreases. john
Wiki User
∙ 15y ago
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A capacitor is a device which stores energy by?
Magic. Look up capacitors on wikipedia!!A capacitor stores electrical charges in its plates.Both wrong. A capacitor stores energy as an electric field developed in the dielectric between its plates. A good dielectric with high permittivity (once called dielectric constant) concentrates this field, allowing more energy to be stored in a capacitor having the same plate area and separation but a dielectric of lower permittivity.
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 a dielectric?
In physics, a dielectric is an insulating (or very poorly conducting) material. The material can be solid, liquid or gaseous. When a voltage difference is applied to top and bottom of a cylinder filled with a dielectric, no current will flow inside the cylinder because, unlike metals, a dielectric has no free-or loosely bound-electrons that can drift through the material. Instead, electric polarization occurs. The positive charges within the dielectric are displaced minutely in the direction of lower voltage, and the negative charges are displaced minutely in the opposite direction. When the molecules constituting the dielectric are polar (like water molecules), the molecules will align in the field, thus contributing to the electric polarization. Inside the cylinder no net charge density will arise because the charges in adjacent volume elements cancel. However, at the top and bottom of the cylinder an uncanceled surface charge will appear, and this surface charge (positive at the low voltage side and negative at the high voltage side) will oppose the electric field associated with the voltage difference. Thus, the polarization of the dielectric reduces the electric field inside the dielectric. Dielectric material is characterized by an intrinsic property called relative permittivity, usually denoted by εr (formerly this was known as the dielectric constant). The relative permittivity describes the ease of the polarization of the material and determines the size of the surface charge densities at the top and bottom of the cylinder. The Coulomb force between two permanent electric point charges placed inside a dielectric medium is 1/εr smaller than it would be in a vacuum due to the polarization of the dielectric medium by the point charges. The quantity of electric energy stored per unit volume of a dielectric medium is proportional to εr. The capacitance of a capacitor filled with a dielectric is a factor εr greater than it would be in vacuum. Reference: http://en.citizendium.org/wiki/DielectricDielectric is a substance that can transport electricity without conducting it.
How do you change time constant of capacitor?
In theory ... on paper where you have ideal components ... a capacitor all by itself doesn't have a time constant. It charges instantly. It only charges exponentially according to a time constant when it's in series with a resistor, and the time constant is (RC). Keeping the same capacitor, you change the time constant by changing the value of the resistor.
What makes the capacitor to store charges?
A capacitor consists of two plates (foils ...) separated by an insulating medium. The insulating medium may be air, oil, a plastic film, and so on, and is known as the dielectric. The charge on the capacitor is actually stored by slightly distorting the molecules in the dielectric. The quality of a dielectric is measured by a factor known as K, and a higher K means that the molecule can store a larger distortion. When we discharge the capacitor, the molecules are allowed to relax to their uncharged state.
What is meant about di-electric constant?
The relative permittivity of a material is its dielectric permittivity expressed as a ratio relative to the permittivity of vacuum.Permittivity is a material property that expresses the force between two point charges in the material. Relative permittivity is the factor by which the electric field between the charges is decreased or increased relative to vacuum.Likewise, relative permittivity is the ratio of the capacitance of a capacitor using that material as a dielectric, compared to a similar capacitor that has vacuum as its dielectric. Relative permittivity is also commonly known as dielectric constant, a term deprecated in physics and engineering.
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.
What is the Difference between dielectric and insulator?
The difference between dielectric and insulator lies in its field of application.Dielectrics are used to store the electric charges, while insulators are used to block the flow of electric charges ( they more or less act like a wall).While all dielectrics are insulators (they don't allow the flow of electric charges through them) all insulators aren't dielectric because they can't store charges unlike dielectrics.
What is magnetic permeability of materials?
Relative permittivity or dielectric constant of a medium is defined as the ratio of force between two charges separated by a certain distance in air or vacuum to the force between the same charges separated by the same distance in the medium.According to American Heritage Dictionary:permittivitySYLLABICATION: per·mit·tiv·i·tyPRONUNCIATION: PERM eh TIV eh TEENOUN: Inflected forms: pl. per·mit·tiv·i·tiesA measure of the ability of a material to resist the formation of an electric field within it. Also called dielectric constant, relative permittivity.
A capacitor is a device which stores energy by?
Magic. Look up capacitors on wikipedia!!A capacitor stores electrical charges in its plates.Both wrong. A capacitor stores energy as an electric field developed in the dielectric between its plates. A good dielectric with high permittivity (once called dielectric constant) concentrates this field, allowing more energy to be stored in a capacitor having the same plate area and separation but a dielectric of lower permittivity.
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.
Explain how the dielectric material or medium of electrical charges affect the value of potential energy?
the dielectric placed between the positive and negative plates of a capacitor prevents the collapse of plates due to so strong attractive forces between them and retains the potential difference between the plates.....
What will happen to the electrostatic force between the two charges if a metal slab is placed between them?
force between two charged particles always depends on their charges , distance between them and the nature of material enclosed in between them (shortly permittivity ).permitivity is defined as the resistance encountered when forming an electric field in the medium, in other words it is defined as how much flux is generated in the medium , this flux generated would be more if the material is a metal.So, metals have high permitivity when compared to non metals or free space .as force is inversely proportional to permitivity , metals increase permitivitty so the net force between the two charges is reduced
What is relative permitivity?
It is the element by which the electric field between the charges is diminished in respect to vacuum. In like manner, relative permittivity is the proportion of the capacitance of a capacitor utilizing that material as a dielectric, contrasted with a comparative capacitor that has vacuum as its dielectric.
What is a dielectric?
In physics, a dielectric is an insulating (or very poorly conducting) material. The material can be solid, liquid or gaseous. When a voltage difference is applied to top and bottom of a cylinder filled with a dielectric, no current will flow inside the cylinder because, unlike metals, a dielectric has no free-or loosely bound-electrons that can drift through the material. Instead, electric polarization occurs. The positive charges within the dielectric are displaced minutely in the direction of lower voltage, and the negative charges are displaced minutely in the opposite direction. When the molecules constituting the dielectric are polar (like water molecules), the molecules will align in the field, thus contributing to the electric polarization. Inside the cylinder no net charge density will arise because the charges in adjacent volume elements cancel. However, at the top and bottom of the cylinder an uncanceled surface charge will appear, and this surface charge (positive at the low voltage side and negative at the high voltage side) will oppose the electric field associated with the voltage difference. Thus, the polarization of the dielectric reduces the electric field inside the dielectric. Dielectric material is characterized by an intrinsic property called relative permittivity, usually denoted by εr (formerly this was known as the dielectric constant). The relative permittivity describes the ease of the polarization of the material and determines the size of the surface charge densities at the top and bottom of the cylinder. The Coulomb force between two permanent electric point charges placed inside a dielectric medium is 1/εr smaller than it would be in a vacuum due to the polarization of the dielectric medium by the point charges. The quantity of electric energy stored per unit volume of a dielectric medium is proportional to εr. The capacitance of a capacitor filled with a dielectric is a factor εr greater than it would be in vacuum. Reference: http://en.citizendium.org/wiki/DielectricDielectric is a substance that can transport electricity without conducting it.
What is mean by dielectric contants?
two equal and opposite charges seprated by a small distance.
What true about the force between charges?
The force between charges decreases as the distance between them increases. Like charges repel each other. Oppostite charges attract each other
