විද්‍යුත් ප්‍රතිරෝධකතාව සහ සන්නායකතාව

විද්‍යුත් ප්‍රතිරෝධකතාව () යනු විද්‍යුත් ධාරාවක් ගලා යෑමට යම් ද්‍රව්‍යයක් කෙතරම් තදින් ප්‍රතිරෝධී වන්නේ ද යන්න මනිනු ලබන මූලික ගුණාංගයකි වේ. අඩු ප්‍රතිරෝධීතාවයක් ඇති ද්‍රව්‍යය හරහා පහසුවෙන් විදුලිය ගලා යයි. ප්‍රතිරෝධීතාවය සාමාන්‍යයෙන් 
 (rho) ග්‍රීක අක්ෂරයෙන් දක්වයි. විද්‍යුත් ප්‍රතිරෝධීතාවය සඳහා වන SI ඒකකය වන්නේ ඕම්-මීටර (Ω⋅m) වේ.

විද්‍යුත් සන්නායකතාව () යනු විද්‍යුත් ප්‍රතිරෝධකතාවයෙහි අනෙක් පසය.  එනම් එය යම් ද්‍රව්‍යයක විද්‍යුත් ධාරාවක් ගෙන යාමට ඇති හැකියාව වේ. එය සාමාන්‍යයෙන්  (සිග්මා) ග්‍රීක අක්ෂරයෙන් දැක්වේ, නමුත් සමහර විට  (kappa) (විශේෂයෙන්ම electrical engineering) සහ  (gamma) භාවිතා වේ. විද්‍යුත් සන්නායකතාවය සඳහා වන SI ඒකකය වන්නේ siemens per metre (S/m) වේ. 

විවිධ ද්‍රව්‍යයන්ගේ ප්‍රතිරෝධීතා සහ සන්නායකතා 

මෙම වගුව විවිධ ද්‍රව්‍යයන්ගේ  දි ප්‍රතිරෝධීතා (), සන්නායකතා සහ temperature coefficient දක්වයි.

+ Resistivity, conductivity, and temperature coefficient for several materials Material Resistivity, , at  (Ω·m) Conductivity, , at  (S/m) Temperature coefficientThe numbers in this column increase or decrease the significand portion of the resistivity. For example, at , the resistivity of silver is . This is calculated as  where  is the resistivity at  (in this case) and  is the temperature coefficient. (K−1) Reference රිදීThe conductivity of metallic silver is not significantly better than metallic copper for most practical purposes – the difference between the two can be easily compensated for by thickening the copper wire by only 3%. However silver is preferred for exposed electrical contact points because corroded silver is a tolerable conductor, but corroded copper is a fairly good insulator, like most corroded metals. තඹCopper is widely used in electrical equipment, building wiring, and telecommunication cables. Annealed copperReferred to as 100% IACS or International Annealed Copper Standard. The unit for expressing the conductivity of nonmagnetic materials by testing using the eddy current method. Generally used for temper and alloy verification of aluminium.     රන්Despite being less conductive than copper, gold is commonly used in electrical contacts because it does not easily corrode. ඇලුමිනියම්Commonly used for overhead power line with steel reinforced (ACSR) Calcium Tungsten තුත්තනාගම්Physical constants . (PDF format; see page 2, table in the right lower corner). Retrieved on 2011-12-17. Cobalt නිකල් Ruthenium Lithium යකඩ ප්ලැටිනම් Tin Gallium NiobiumMaterial properties of niobium. Carbon steel (1010)AISI 1010 Steel, cold drawn. Matweb ඊයම්  Galinstan   Titanium Grain oriented electrical steel Manganin(see also Table of Resistivity. hyperphysics.phy-astr.gsu.edu) ConstantanJohn O'Malley (1992) Schaum's outline of theory and problems of basic circuit analysis, p. 19, McGraw-Hill Professional,  Stainless steel18% chromium and 8% nickel austenitic stainless steelGlenn Elert (ed.), "Resistivity of steel", The Physics Factbook, retrieved and archived 16 June 2011. Mercury Manganese   NichromeNickel-iron-chromium alloy commonly used in heating elements. Carbon (graphite)parallel to basal planeGraphite is strongly anisotropic. to   to  Hugh O. Pierson, Handbook of carbon, graphite, diamond, and fullerenes: properties, processing, and applications, p. 61, William Andrew, 1993 . Carbon (amorphous) to   to  Y. Pauleau, Péter B. Barna, P. B. Barna (1997) Protective coatings and thin films: synthesis, characterization, and applications, p. 215, Springer, . Carbon (graphite)perpendicular to basal plane  GaAs to  to   GermaniumThe resistivity of semiconductors depends strongly on the presence of impurities in the material.2.17  Sea waterCorresponds to an average salinity of 35 g/kg at . Physical properties of sea water . Kayelaby.npl.co.uk. Retrieved on 2011-12-17. Swimming pool waterThe pH should be around 8.4 and the conductivity in the range of 2.5–3 mS/cm. The lower value is appropriate for freshly prepared water. The conductivity is used for the determination of TDS (total dissolved particles). to  to . chemistry.stackexchange.com Drinking waterThis value range is typical of high quality drinking water and not an indicator of water quality to  to   Silicon  Wood (damp) to  to Transmission Lines data . Transmission-line.net. Retrieved on 2014-02-03. Deionized waterConductivity is lowest with monatomic gases present; changes to  upon complete de-gassing, or to  upon equilibration to the atmosphere due to dissolved CO2  Ultrapure water ASTM D1125 Standard Test Methods for Electrical Conductivity and Resistivity of WaterASTM D5391 Standard Test Method for Electrical Conductivity and Resistivity of a Flowing High Purity Water Sample Glass to  to    Carbon (diamond)~ Lawrence S. Pan, Don R. Kania, Diamond: electronic properties and applications, p. 140, Springer, 1994 . Hard rubber  Air to ~ to   Wood (oven dry) to  to  Sulfur  Fused quartz  PET  PTFE (teflon) to  to  

ආශ්‍රිත

 Charge transport mechanisms
 Chemiresistor
 Classification of materials based on permittivity
 Conductivity near the percolation threshold
 Contact resistance
 Electrical resistivities of the elements (data page)
 Electrical resistivity tomography
 Sheet resistance
 SI electromagnetism units
 Skin effect
 Spitzer resistivity
 Dielectric strength

 සටහන් 

මූලාශ්‍ර

භාහිර සබැඳි


Comparison of the electrical conductivity of various elements in WolframAlpha

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Category:Physical quantities
Category:Materials science