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Yes, these fall in a class called metamaterials.

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What is the effect of temperature on dielectric constant of a dielectric?

Usually, dielectric materials have permanent dipoles. As temperature increases, the molecules in the dielectric have more thermal energy and therefore, the amplitude of random motion is greater. This means that the molecules are less closely aligned with each other (even in the presence of an electric field). Hence, the dielectric constant reduces.


Why is dielectric constant for metals is infinity?

It is not infinite. At some extreme values electron-positron pairs will start forming rapidly what will result current flow. However from practical standpoint vacuum dielectric strength is limited by field emission from electrodes. Best results are about 40MV/m , what is far worse than some good dielectrics can provide.


What does it mean if you have a high value for youngs modulus 8333.3 compared to a low value 1200?

Young's modulus is stress/strain. So if the modulus is high, it means that the stress value is greater compare to that of the material where the modulus is low. or in other words, the strain is very less compared to that of the material having low Young's modulus. So it tells that, if a material has high Young's modulus, the material requires more load for deformation of shape (within elastic limit).


What is the advantage of a 'l' or 'i' shaped beam?

There is many advantages some of the advantages are less weight, less material and very high strength. (:


What is meant by non constant envelope modulation?

A constant-envelope modualtion is a modualtion scheme in which the amplitude of the modualted tone remains constant with time. Main advantage of such modualtion schmes is that they relax the linearity requirements of the power amplifier (PA) and hence a less linear and more efficient PA can be used. Most modualtion schemes are not constant-envelope. For example, BPSK, QPSK, 16-QAM are not constant-envelope. Few modualtion schemes such as GFSK are constant-envelope.

Related Questions

What is the effect of temperature on dielectric constant of a dielectric?

Usually, dielectric materials have permanent dipoles. As temperature increases, the molecules in the dielectric have more thermal energy and therefore, the amplitude of random motion is greater. This means that the molecules are less closely aligned with each other (even in the presence of an electric field). Hence, the dielectric constant reduces.


What is the much more polar solvent?

Formamide is the most polar solvent. It has a dipole moment of 3.73 and a dielectric constant of 109. As a comparison, water has a dipole moment of 1.85 and a dielectric constant of 80. The higher the dipole moment value and the dielectric constant, the more polar the solvent. At the opposite, the less polar solvents are hexane, benzene and carbontetrachloride.


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.


What happens to Dielectric strength when heated?

When a dielectric material is heated, its dielectric strength typically decreases. This is because heat can modify the material's properties, structure, and ability to resist electric fields. As a result, the material may become more conductive and less effective at insulating against electrical charges.


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.


Why does the electric field inside a dielectric decrease when it is placed in an external electric field?

The net electric field inside a dielectric decreases due to polarization. The external electric field polarizes the dielectric and an electric field is produced due to this polarization. This internal electric field will be opposite to the external electric field and therefore the net electric field inside the dielectric will be less.


What is the advantage of having a reduced gametophyte when compared to non vascular plants?

A reduced gametophyte has to waste less material for gamete formation


Why don't we have less homework?

Teachers assign homework to help you understand the material - so long as there are students who are having trouble in the class, there will be homework.


If material is heated and expands the density of the material will?

This relies on 3 things. The Pressure, volume and temperature of a Gas is all related. If the pressure is kept the same and temperature increased. The Volume (of the container) must be increased. If the Volume (of the container) is kept constant and temperature is increased the Pressure will increase. A rough idea of what will happen can be worked out by, pV=cT Where p is the pressure, V is the volume of the container, c is a constant, T is the temperature.


What materials are naturally static-resistant?

There is no material that is naturally static resistent. The time for which the static charge is present on the material depends on its Relaxation Time. This is directly proportional to the ratio of dielectric constant and its conductivity. Thus conducting materials have very short relaxation time so we feel no static charge is developed on it. Thus for practical purpose most of the metals are static resistant.


What is better the one having less or more Thermal Expansion Coefficient?

Depends on your application. The Thermal Expansion Coefficient is a number which represents how much a material will physically expand with an increase in temperature. If you want it to grow as it heats, it is the better material.


Why Ghana is less productive?

less row material available