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Is there any material having dielectric constant less than 1?
Yes, these fall in a class called metamaterials.
If the distance between the parallel plate capacitor is reduced to half and a dielectric of dielectric constant k is introduced then how does electric field varies?
From the formula, E = V/d, where V is the voltage and d is the distance, it can be seen that the electric field and the distance are inversely related. Thus, as the distance between the parallel plate capacitors is reduced to half, the electric field is increased twice. Moreover, is a dielectric constant k is introduced, the capacitance will increase. This direct relationship can be seen in the formula, C = [k(Єo)A]/d, where k is the dielectric constant. The lowest possible value of k is 1; and that is when the dielectric is a vacuum. Other dielectric constants are greater than 1, such as teflon which has a dielectric value of 2.1 As the capacitance increases, the electric field also increases. (E = 1/2(CV^2))
What is dielectric stress?
The dielectric stress is the stress placed upon a material when a voltage is placed across it.
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.
Is polypropylene better than polystyrene?
That depends on how you define "better" and what you're using it for.
What is the die electric constant for insulators?
There is no more the dielectric constant for insulators than the colour for shirts. Every shirt has a colour, and every insulator has a dielectric constant. Find out what material your insulator is, then look in Kaye & Labey or any good handbook for radio and electronics engineers.
What happens to a capacitance if the volume is filled with material having a dielectric constant of 5?
The capacitance will increase. When the volume is filled with a material with a dielectric constant greater than 1, the capacitance of the capacitor increases by a factor equal to the material's dielectric constant. This is because the electric field is effectively reduced within the material, allowing more charge to be stored for the same voltage.
Is there any material having dielectric constant less than 1?
Yes, these fall in a class called metamaterials.
If the distance between the parallel plate capacitor is reduced to half and a dielectric of dielectric constant k is introduced then how does electric field varies?
From the formula, E = V/d, where V is the voltage and d is the distance, it can be seen that the electric field and the distance are inversely related. Thus, as the distance between the parallel plate capacitors is reduced to half, the electric field is increased twice. Moreover, is a dielectric constant k is introduced, the capacitance will increase. This direct relationship can be seen in the formula, C = [k(Єo)A]/d, where k is the dielectric constant. The lowest possible value of k is 1; and that is when the dielectric is a vacuum. Other dielectric constants are greater than 1, such as teflon which has a dielectric value of 2.1 As the capacitance increases, the electric field also increases. (E = 1/2(CV^2))
What is the ratio of forces between two masses kept at a certain distance in the air to the force between them when kept in any other medium?
The ratio of forces between two masses in air to the force between them in any other medium is determined by the medium's relative permittivity or dielectric constant. In a medium with a dielectric constant other than air, the force between the masses will be reduced by a factor equal to the medium's dielectric constant.
Is polystyrene ball heavier than iron ball?
No, iron is denser and heavier than polystyrene. An iron ball would weigh more than a polystyrene ball of the same size.
Why energy at constant pressure greater more than at constant volume?
high
Define Velocity of propagation for co-axial cable?
The velocity factor is the speed at which an RF signal travels through a material compared to the speed the same signal travels through a vacuum. The velocity of propagation is inversely proportional to the dielectric constant. Lowering the constant increases the velocity.Generally, the higher the velocity factor, the lower the loss through a coaxial cable.General Rules for Coaxial CableD = diameter of insulation under the shieldd = diameter of inner conductor.Velocity Factor, Velocity of Propagation, VpThe higher the velocity factor, the lower the loss through the cable.Raising the D/d has no effect on VpRaising the dielectric constant lowers VpCapacitanceRaising the D/d ratio lowers capacitanceRaising the dielectric constant raises capacitanceImpedance Raising the D/d radio raises impedanceRaising the dielectric constant lowers impedanceAttenuation or LossRaising the D/d ratio lowers attenuationRaising the dielectric constant raises attenuationSo in simpler terms the larger amount of dielectric between the center conductor and sheath equals less loss in RF. Trunk cables have less loss than feeder legs.
Is polystyrene less dence than water?
Yes, polystyrene is less dense than water. Water has a density of 1 g/cm^3, while polystyrene typically has a density of about 1.05 g/cm^3. This means that polystyrene will float on water.
What is HIPS plastic?
HIPS High Impact Polystyrene is particularly suitable for thermoforming, it is a tough, rigid material and its high impact strength means it can be guillotined, punched, routered or sawn without difficulty.
Can polystyrene sink in water?
No, polystyrene is less dense than water, so it will float on the water's surface rather than sink.
Is rubber heavier than polystyrene?
Yes.
