noun
definition
The ability of a material to conduct electricity, heat, fluid or sound
definition
The reciprocal of resistivity
Examples of conductivity in a Sentence
The conductivity gives us the amount of electricity conveyed per second under a definite electromotive force.
The principal points of difference are that (I) the magnetic permeability, unlike the electric conductivity, which is independent of the strength of the current, is not in general constant; (2) there is no perfect insulator for magnetic induction, which will pass more or less freely through all known substances.
For example, a rise in temperature of the bath causes an increase in its conductivity, so that a lower E.M.F.
Others have arranged a means of obtaining high conductivity wire from cathode-copper without fusion, by depositing the metal in the form of a spiral strip on a cylinder, the strip being subsequently drawn down in the usual way; at present, however, the ordinary methods of wire production are found to be cheaper.
Abrupt alterations, take place in its density, specific heat, thermo-electric quality, electrical conductivity, temperature-coefficient of electrical resistance, and in some at least of its mechanical properties.
The total magnetic induction or flux corresponds to the current of electricity (practically measured in amperes); the induction or flux density B to the density of the current (number of amperes to the square centimetre of section); the magnetic permeability to the specific electric conductivity; and the line integral of the magnetic force, sometimes called the magnetomotive force, to the electro-motive force in the circuit.
Moreover, the variation of thermal conductivity with temperature is small and uncertain, whereas the variation of electrical conductivity is large and can be accurately determined, and may therefore be legitimately utilized for eliminating the external heat-loss.
From a comparison of this work with that of Lorenz, it is evident that the values of the conductivity vary widely with the purity of the material, and cannot be safely applied to other specimens than those for which they were found.
Conductivity and viscosity in a gas should vary in a similar manner since each depends on diffusion in a similar way.
By similar reasoning the thermal conductivity of a gas should be independent of the density.
The question of the variation of conductivity with temperature is more difficult.
If the effects depended merely on the velocity of translation of the molecules, both conductivity and viscosity should increase directly as the square root of the absolute temperature; but the mean free path also varies in a manner which cannot be predicted by theory and which appears to be different for different gases (Rayleigh, Proc. R.S., January 1896).
The conductivity probably changes with temperature in the same way, being proportional to the product of the viscosity and the specific heat; but the experimental investigation presents difficulties on account of the necessity of eliminating the effects of radiation and convection, and the results of different observers often differ considerably from theory and from each other.
The conductivity of liquids has been investigated by similar methods, generally variations of the thin plate or guard-ring method.
It appears probable that the conductivity of a liquid increases considerably with rise of temperature, although the contrary would appear from the work of Lees.
Among the properties of the neuron is conductivity in all directions.
Thus, applied to a potential, it gives the direction and magnitude of the force; to a distribution of temperature in a conducting solid, it gives (when multiplied by the conductivity) the flux of heat, &c.
A third great use of the electroscope is therefore to detect electric conductivity either in the air or in any other body.
He made many measurements of the electric conductivity of different solids and liquids, by comparing the intensity of the electric shock taken through his body and various conductors.
He discovered that they had the power of affecting the electric conductivity of materials when in a state of powder, the majority of metallic filings increasing in conductivity.
To-day, by reason of other uses to which electricity is applied, electrically deposited copper of high conductivity is in everincreasing demand, and commands a higher price than copper refined by fusion.
Such an irregular distribution of the bath, with strong copper sulphate solution from the anode at the bottom and acid solution from the cathode at the top, not only alters the conductivity in different strata and so causes irregular current-distribution, but may lead to the current-density in the upper layers being too great for the proportion of copper there present.
He was specially noted for his discovery of the electrical conductivity of bismuth and other metals, and for his pioneer work in wireless telegraphy.
Another discussed conduction in curved sheets; a third the distribution of electricity in two influencing spheres; a fourth the deter mination of the constant on which depends the intensity of induced currents; while others were devoted to Ohm's law, the motion of electricity in submarine cables, induced magnetism, &c. In other papers, again, various miscellaneous topics were treated - the thermal conductivity of iron, crystalline reflection and refraction, certain propositions in the thermodynamics of solution and vaporization, &c. An important part of his work was contained in his Vorlesungen fiber mathematische Physik (1876), in which the principles of dynamics, as well as various special problems, were treated in a somewhat novel and original manner.
Hydrobromic acid is one of the "strong" acids, being ionized to a very large extent even in concentrated solution, as shown by the molecular conductivity increasing by only a small amount over a wide range offdilution.
His later researches included observations on the conductivity of various substances for heat, and on the effect of pressure on the temperature of fusion of different bodies.
The basis of Fourier's work was his clear conception and definition of conductivity.
Thomson, on the other hand, set to work to overcome the difficulty by improvement in the manufacture of cables, and first of all in the production of copper of high conductivity and the construction of apparatus which would readily respond to the slightest variation of the current in the cable.
In this way the metal, owing to its high conductivity and low specific heat as compared to that of water, is kept at a temperature far below its melting point if the water is renewed quickly enough.
The white storage elements consist of a highly heat resistant material based on special fused alumina which has very high heat capacity and conductivity.
Barriers with a low hydraulic conductivity can be produced by adding bentonite to a locally available soil.
You could measure conductivity of your PEG solution to get a clue how much ionic stuff is present.
The measurement of thermal diffusivity by laser flash is an alternative way of determining the thermal conductivity of liquid alloys.
Water has the highest thermal conductivity of any liquid.
These results could re-open the discussion on the mechanism of ionic conductivity in these materials.
Void filling should obviously link with changes in the soil's hydraulic conductivity.
Explain how band theory can account for the electrical conductivity of the elements in groups I - IV.
We will now revisit the anisotropic thermal conductivity of quartz.
The low conductivity of char will cause a steep thermal gradient across the char layer.
It is clear, however, that the flow is severely perturbed by the enhanced ionospheric conductivity caused by particle precipitation into the E-region.
The process of lapping makes the heatsink base smooth to a near mirror finish, which improves heat conductivity.
Other Methods These, such as soil conductivity meters, metal detectors and micro gravity, exist but will not be discussed here.
High conductivity copper is the most common form of the metal available.
A similar model was proposed with hydroxyl ions hydrogen bonding to surface H causing polarization and conductivity.
Furthermore, the conductivity was found to be sensitive to small changes in the composition, a property characteristic of doped semiconductors.
The exact mix ratio was found to be of vital importance when balancing good conductivity against low shrinkage.
The high thermal conductivity of the pan acts to rapidly thaw most items.
The above series of salts show striking differences in their behaviour towards reagents; thus, aqueous solutions of the luteo chlorides are strongly ionized, as is shown by their high electric conductivity; and all their chlorine is precipitated on the addition of silver nitrate solution.
The purpureo chloride has only two-thirds of its chlorine precipitated on the addition of silver nitrate, and the electric conductivity is much less than that of the luteo chloride; again in the praseosalts only one-third of the chlorine is precipitated by silver nitrate, the conductivity again falling; while in the triammine salts all ionization has disappeared.
His data for the thermal conductivity of various metals were for long the most trustworthy at the disposal of physicists, and his determination of the ohm in terms of the specific resistance of mercury showed remarkable skill in quantitative research.