All Stars are basically plasma and are like controlled hydrogen fusion bombs ever single day. The lightest element on the periodic chart is Hydrogen and from hydrogen it becomes helium and on down the line. This is why when people say the earth and people are made of Stardust they are correct in this. Because earth is star dust from the elements being slowly manufactured by suns (possibly the one above your head outside if it is daytime).
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https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity#Plasma
Plasma[edit]
Plasmas are very good conductors and electric potentials play an important role.
The potential as it exists on average in the space between charged particles, independent of the question of how it can be measured, is called the plasma potential, or space potential. If an electrode is inserted into a plasma, its potential generally lies considerably below the plasma potential, due to what is termed a Debye sheath. The good electrical conductivity of plasmas makes their electric fields very small. This results in the important concept of quasineutrality, which says the density of negative charges is approximately equal to the density of positive charges over large volumes of the plasma (ne = ⟨Z⟩>ni), but on the scale of the Debye length there can be charge imbalance. In the special case that double layers are formed, the charge separation can extend some tens of Debye lengths.
The magnitude of the potentials and electric fields must be determined by means other than simply finding the net charge density. A common example is to assume that the electrons satisfy the Boltzmann relation:
Differentiating this relation provides a means to calculate the electric field from the density:
(∇ is the vector gradient operator; see nabla symbol and gradient for more information.)
It is possible to produce a plasma that is not quasineutral. An electron beam, for example, has only negative charges. The density of a non-neutral plasma must generally be very low, or it must be very small. Otherwise, the repulsive electrostatic force dissipates it.
In astrophysical plasmas, Debye screening prevents electric fields from directly affecting the plasma over large distances, i.e., greater than the Debye length. However, the existence of charged particles causes the plasma to generate, and be affected by, magnetic fields. This can and does cause extremely complex behavior, such as the generation of plasma double layers, an object that separates charge over a few tens of Debye lengths. The dynamics of plasmas interacting with external and self-generated magnetic fields are studied in the academic discipline of magnetohydrodynamics.
Plasma is often called the fourth state of matter after solid, liquids and gases.[19][20] It is distinct from these and other lower-energy states of matter. Although it is closely related to the gas phase in that it also has no definite form or volume, it differs in a number of ways, including the following:
| Property | Gas | Plasma |
|---|---|---|
| Electrical conductivity | Very low: air is an excellent insulator until it breaks down into plasma at electric field strengths above 30 kilovolts per centimeter.[21] | Usually very high: for many purposes, the conductivity of a plasma may be treated as infinite. |
| Independently acting species | One: all gas particles behave in a similar way, influenced by gravity and by collisions with one another. | Two or three: electrons, ions, protons and neutrons can be distinguished by the sign and value of their charge so that they behave independently in many circumstances, with different bulk velocities and temperatures, allowing phenomena such as new types of waves and instabilities. |
| Velocity distribution | Maxwellian: collisions usually lead to a Maxwellian velocity distribution of all gas particles, with very few relatively fast particles. | Often non-Maxwellian: collisional interactions are often weak in hot plasmas and external forcing can drive the plasma far from local equilibrium and lead to a significant population of unusually fast particles. |
| Interactions | Binary: two-particle collisions are the rule, three-body collisions extremely rare. | Collective: waves, or organized motion of plasma, are very important because the particles can interact at long ranges through the electric and magnetic forces. |
Resistivity and conductivity of various materials[edit]
- A conductor such as a metal has high conductivity and a low resistivity.
- An insulator like glass has low conductivity and a high resistivity.
- The conductivity of a semiconductor is generally intermediate, but varies widely under different conditions, such as exposure of the material to electric fields or specific frequencies of light, and, most important, with temperature and composition of the semiconductor material.
The degree of semiconductors doping makes a large difference in conductivity. To a point, more doping leads to higher conductivity. The conductivity of a solution of water is highly dependent on its concentration of dissolved salts, and other chemical species that ionize in the solution. Electrical conductivity of water samples is used as an indicator of how salt-free, ion-free, or impurity-free the sample is; the purer the water, the lower the conductivity (the higher the resistivity). Conductivity measurements in water are often reported as specific conductance, relative to the conductivity of pure water at 25 °C. An EC meter is normally used to measure conductivity in a solution. A rough summary is as follows:
| Material | Resistivity, ρ (Ω·m) |
|---|---|
| Superconductors | 0 |
| Metals | 10−8 |
| Semiconductors | Variable |
| Electrolytes | Variable |
| Insulators | 1016 |
| Superinsulators | ∞ |
This table shows the resistivity (ρ), conductivity and temperature coefficient of various materials at 20 °C (68 °F; 293 K).
| Material | Resistivity, ρ, at 20 °C (Ω·m) | Conductivity, σ, at 20 °C (S/m) | Temperature coefficient[c] (K−1) | Reference |
|---|---|---|---|---|
| Silver[d] | 1.59×10−8 | 6.30×107 | 3.80×10−3 | [22][23] |
| Copper[e] | 1.68×10−8 | 5.96×107 | 4.04×10−3 | [24][25] |
| Annealed copper[f] | 1.72×10−8 | 5.80×107 | 3.93×10−3 | [26] |
| Gold[g] | 2.44×10−8 | 4.11×107 | 3.40×10−3 | [22] |
| Aluminium[h] | 2.65×10−8 | 3.77×107 | 3.90×10−3 | [22] |
| Calcium | 3.36×10−8 | 2.98×107 | 4.10×10−3 | |
| Tungsten | 5.60×10−8 | 1.79×107 | 4.50×10−3 | [22] |
| Zinc | 5.90×10−8 | 1.69×107 | 3.70×10−3 | [27] |
| Cobalt[i] | 6.24×10−8 | 1.60×107 | 7.00×10−3[29][unreliable source?] | |
| Nickel | 6.99×10−8 | 1.43×107 | 6.00×10−3 | |
| Ruthenium[i] | 7.10×10−8 | 1.41×107 | ||
| Lithium | 9.28×10−8 | 1.08×107 | 6.00×10−3 | |
| Iron | 9.70×10−8 | 1.03×107 | 5.00×10−3 | [22] |
| Platinum | 10.6×10−8 | 9.43×106 | 3.92×10−3 | [22] |
| Tin | 10.9×10−8 | 9.17×106 | 4.50×10−3 | |
| Gallium | 14.0×10−8 | 7.10×106 | 4.00×10−3 | |
| Niobium | 14.0×10−8 | 7.00×106 | [30] | |
| Carbon steel (1010) | 14.3×10−8 | 6.99×106 | [31] | |
| Lead | 22.0×10−8 | 4.55×106 | 3.90×10−3 | [22] |
| Galinstan | 28.9×10−8 | 3.46×106 | [32] | |
| Titanium | 42.0×10−8 | 2.38×106 | 3.80×10−3 | |
| Grain oriented electrical steel | 46.0×10−8 | 2.17×106 | [33] | |
| Manganin | 48.2×10−8 | 2.07×106 | 0.002×10−3 | [34] |
| Constantan | 49.0×10−8 | 2.04×106 | 0.008×10−3 | [35] |
| Stainless steel[j] | 69.0×10−8 | 1.45×106 | 0.94×10−3 | [36] |
| Mercury | 98.0×10−8 | 1.02×106 | 0.90×10−3 | [34] |
| Manganese | 144×10−8 | 6.94×105 | ||
| Nichrome[k] | 110×10−8 | 6.70×105 [citation needed] | 0.40×10−3 | [22] |
| Carbon (graphite) parallel to basal plane[l] | 250×10−8 to 500×10−8 | 2×105 to 3×105 [citation needed] | [4] | |
| Carbon (amorphous) | 0.5×10−3 to 0.8×10−3 | 1.25×103 to 2.00×103 | −0.50×10−3 | [22][37] |
| Carbon (graphite) perpendicular to basal plane | 3.0×10−3 | 3.3×102 | [4] | |
| GaAs | 10−3 to 108[clarification needed] | 10−8 to 103[dubious ] | [38] | |
| Germanium[m] | 4.6×10−1 | 2.17 | −48.0×10−3 | [22][23] |
| Sea water[n] | 2.1×10−1 | 4.8 | [39] | |
| Swimming pool water[o] | 3.3×10−1 to 4.0×10−1 | 0.25 to 0.30 | [40] | |
| Drinking water[p] | 2×101 to 2×103 | 5×10−4 to 5×10−2 | [citation needed] | |
| Silicon[m] | 2.3×103 | 4.35×10−4 | −75.0×10−3 | [41][22] |
| Wood (damp) | 103 to 104 | 10−4 to 10−3 | [42] | |
| Deionized water[q] | 1.8×105 | 4.2×10−5 | [43] | |
| Glass | 1011 to 1015 | 10−15 to 10−11 | [22][23] | |
| Carbon (diamond) | 1012 | ~10−13 | [44] | |
| Hard rubber | 1013 | 10−14 | [22] | |
| Air | 109 to 1015 | ~10−15 to 10−9 | [45][46] | |
| Wood (oven dry) | 1014 to 1016 | 10−16 to 10−14 | [42] | |
| Sulfur | 1015 | 10−16 | [22] | |
| Fused quartz | 7.5×1017 | 1.3×10−18 | [22] | |
| PET | 1021 | 10−21 | ||
| Teflon | 1023 to 1025 | 10−25 to 10−23 |
The effective temperature coefficient varies with temperature and purity level of the material. The 20 °C value is only an approximation when used at other temperatures. For example, the coefficient becomes lower at higher temperatures for copper, and the value 0.00427 is commonly specified at 0 °C.[47]
The extremely low resistivity (high conductivity) of silver is characteristic of metals. George Gamow tidily summed up the nature of the metals' dealings with electrons in his popular science book One, Two, Three...Infinity (1947):
More technically, the free electron model gives a basic description of electron flow in metals.
Wood is widely regarded as an extremely good insulator, but its resistivity is sensitively dependent on moisture content, with damp wood being a factor of at least 1010 worse insulator than oven-dry.[42] In any case, a sufficiently high voltage – such as that in lightning strikes or some high-tension power lines – can lead to insulation breakdown and electrocution risk even with apparently dry wood.[citation needed]
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