විද්‍යුත් ප්‍රතිරෝධකතාව සහ සන්නායකතාව

(Electrical resistivity and conductivity වෙතින් යළි-යොමු කරන ලදි)

විද්‍යුත් ප්‍රතිරෝධකතාව (ඉංග්‍රීසි:  electrical resistivity, specific electrical resistance හෝ volume resistivity) 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 ρ (rho) ග්‍රීක අක්ෂරයෙන් දක්වයි. විද්‍යුත් ප්‍රතිරෝධීතාවය සඳහා වන SI ඒකකය වන්නේ ඕම්-මීටර (Ω⋅m) වේ.[1][2][3]

Resistivity
Common symbols
ρ
SI unitohm meter (Ω⋅m)
In SI base unitskg⋅m3⋅s−3⋅A−2
Derivations from
other quantities
Dimension
Conductivity
Common symbols
σ, κ, γ
SI unitsiemens per metre (S/m)
In SI base unitskg−1⋅m−3⋅s3⋅A2
Derivations from
other quantities
Dimension

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

විවිධ ද්‍රව්‍යයන්ගේ ප්‍රතිරෝධීතා සහ සන්නායකතා සංස්කරණය

මෙම වගුව විවිධ ද්‍රව්‍යයන්ගේ 20 °C (68 °F; 293 K) දි ප්‍රතිරෝධීතා (ρ), සන්නායකතා සහ temperature coefficient දක්වයි.

Resistivity, conductivity, and temperature coefficient for several materials
Material Resistivity, ρ,
at 20 °C (Ω·m)
Conductivity, σ,
at 20 °C (S/m)
Temperature
coefficient[lower-alpha 1] (K−1)
Reference
රිදී[lower-alpha 2] 1.59×10−8 6.30×107 3.80×10−3 [4][5]
තඹ[lower-alpha 3] 1.68×10−8 5.96×107 4.04×10−3 [6][7]
Annealed copper[lower-alpha 4] 1.72×10−8 5.80×107 3.93×10−3 [8]
රන්[lower-alpha 5] 2.44×10−8 4.11×107 3.40×10−3 [4]
ඇලුමිනියම්[lower-alpha 6] 2.65×10−8 3.77×107 3.90×10−3 [4]
Calcium 3.36×10−8 2.98×107 4.10×10−3
Tungsten 5.60×10−8 1.79×107 4.50×10−3 [4]
තුත්තනාගම් 5.90×10−8 1.69×107 3.70×10−3 [9]
Cobalt[lower-alpha 7] 6.24×10−8 1.60×107 7.00×10−3[11]
[unreliable source?]
නිකල් 6.99×10−8 1.43×107 6.00×10−3
Ruthenium[lower-alpha 7] 7.10×10−8 1.41×107
Lithium 9.28×10−8 1.08×107 6.00×10−3
යකඩ 9.70×10−8 1.03×107 5.00×10−3 [4]
ප්ලැටිනම් 10.6×10−8 9.43×106 3.92×10−3 [4]
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 [12]
Carbon steel (1010) 14.3×10−8 6.99×106 [13]
ඊයම් 22.0×10−8 4.55×106 3.90×10−3 [4]
Galinstan 28.9×10−8 3.46×106 [14]
Titanium 42.0×10−8 2.38×106 3.80×10−3
Grain oriented electrical steel 46.0×10−8 2.17×106 [15]
Manganin 48.2×10−8 2.07×106 0.002×10−3 [16]
Constantan 49.0×10−8 2.04×106 0.008×10−3 [17]
Stainless steel[lower-alpha 8] 69.0×10−8 1.45×106 0.94×10−3 [18]
Mercury 98.0×10−8 1.02×106 0.90×10−3 [16]
Manganese 144×10−8 6.94×105
Nichrome[lower-alpha 9] 110×10−8 6.70×105
[තහවුරු කර නොමැත]
0.40×10−3 [4]
Carbon (graphite)
parallel to basal plane[lower-alpha 10]
250×10−8 to 500×10−8 2×105 to 3×105
[තහවුරු කර නොමැත]
[19]
Carbon (amorphous) 0.5×10−3 to 0.8×10−3 1.25×103 to 2.00×103 −0.50×10−3 [4][20]
Carbon (graphite)
perpendicular to basal plane
3.0×10−3 3.3×102 [19]
GaAs 10−3 to 108
[පැහැදීම ඇවැසිය]
10−8 to 103
[dubious ]
[21]
Germanium[lower-alpha 11] 4.6×10−1 2.17 −48.0×10−3 [4][5]
Sea water[lower-alpha 12] 2.1×10−1 4.8 [22]
Swimming pool water[lower-alpha 13] 3.3×10−1 to 4.0×10−1 0.25 to 0.30 [23]
Drinking water[lower-alpha 14] 2×101 to 2×103 5×10−4 to 5×10−2 [තහවුරු කර නොමැත]
Silicon[lower-alpha 11] 2.3×103 4.35×10−4 −75.0×10−3 [24][4]
Wood (damp) 103 to 104 10−4 to 10−3 [25]
Deionized water[lower-alpha 15] 1.8×105 4.2×10−5 [26]
Ultrapure water 1.82×109 5.49×10−10 [27][28]
Glass 1011 to 1015 10−15 to 10−11 [4][5]
Carbon (diamond) 1012 ~10−13 [29]
Hard rubber 1013 10−14 [4]
Air 109 to 1015 ~10−15 to 10−9 [30][31]
Wood (oven dry) 1014 to 1016 10−16 to 10−14 [25]
Sulfur 1015 10−16 [4]
Fused quartz 7.5×1017 1.3×10−18 [4]
PET 1021 10−21
PTFE (teflon) 1023 to 1025 10−25 to 10−23

ආශ්‍රිත සංස්කරණය

සටහන් සංස්කරණය

  1. The numbers in this column increase or decrease the significand portion of the resistivity. For example, at 30 °C (303 K), the resistivity of silver is 1.65×10−8. This is calculated as Δρ = α ΔT ρ0 where ρ0 is the resistivity at 20 °C (in this case) and α is the temperature coefficient.
  2. The 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.
  3. Copper is widely used in electrical equipment, building wiring, and telecommunication cables.
  4. Referred 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.
  5. Despite being less conductive than copper, gold is commonly used in electrical contacts because it does not easily corrode.
  6. Commonly used for overhead power line with steel reinforced (ACSR)
  7. 7.0 7.1 Cobalt and ruthenium are considered to replace copper in integrated circuits fabricated in advanced nodes[10]
  8. 18% chromium and 8% nickel austenitic stainless steel
  9. Nickel-iron-chromium alloy commonly used in heating elements.
  10. Graphite is strongly anisotropic.
  11. 11.0 11.1 The resistivity of semiconductors depends strongly on the presence of impurities in the material.
  12. Corresponds to an average salinity of 35 g/kg at 20 °C.
  13. The 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).
  14. This value range is typical of high quality drinking water and not an indicator of water quality
  15. Conductivity is lowest with monatomic gases present; changes to 12×10−5 upon complete de-gassing, or to 7.5×10−5 upon equilibration to the atmosphere due to dissolved CO2

මූලාශ්‍ර සංස්කරණය

  1. Lowrie, William (2007). Fundamentals of Geophysics. Cambridge University Press. pp. 254–55. ISBN 978-05-2185-902-8. සම්ප්‍රවේශය March 24, 2019.
  2. Kumar, Narinder (2003). Comprehensive Physics for Class XII. New Delhi: Laxmi Publications. pp. 280–84. ISBN 978-81-7008-592-8. සම්ප්‍රවේශය March 24, 2019.
  3. Bogatin, Eric (2004). Signal Integrity: Simplified. Prentice Hall Professional. p. 114. ISBN 978-0-13-066946-9. සම්ප්‍රවේශය March 24, 2019.
  4. 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 4.12 4.13 4.14 Raymond A. Serway (1998). Principles of Physics (2nd ed.). Fort Worth, Texas; London: Saunders College Pub. p. 602. ISBN 978-0-03-020457-9.
  5. 5.0 5.1 5.2 David Griffiths (1999) [1981]. "7 Electrodynamics". In Alison Reeves (ed.). Introduction to Electrodynamics (3rd ed.). Upper Saddle River, New Jersey: Prentice Hall. p. 286. ISBN 978-0-13-805326-0. OCLC 40251748.
  6. Matula, R.A. (1979). "Electrical resistivity of copper, gold, palladium, and silver". Journal of Physical and Chemical Reference Data. 8 (4): 1147. Bibcode:1979JPCRD...8.1147M. doi:10.1063/1.555614. S2CID 95005999.
  7. Douglas Giancoli (2009) [1984]. "25 Electric Currents and Resistance". In Jocelyn Phillips (ed.). Physics for Scientists and Engineers with Modern Physics (4th ed.). Upper Saddle River, New Jersey: Prentice Hall. p. 658. ISBN 978-0-13-149508-1.
  8. "Copper wire tables". United States National Bureau of Standards. සම්ප්‍රවේශය 3 පෙබරවාරි 2014 – via Internet Archive - archive.org (archived 2001-03-10).
  9. Physical constants සංරක්ෂණය කළ පිටපත 2011-11-23 at the Wayback Machine. (PDF format; see page 2, table in the right lower corner). Retrieved on 2011-12-17.
  10. IITC – Imec Presents Copper, Cobalt and Ruthenium Interconnect Results
  11. "Temperature Coefficient of Resistance | Electronics Notes".
  12. Material properties of niobium.
  13. AISI 1010 Steel, cold drawn. Matweb
  14. Karcher, Ch.; Kocourek, V. (December 2007). "Free-surface instabilities during electromagnetic shaping of liquid metals". Proceedings in Applied Mathematics and Mechanics. 7 (1): 4140009–4140010. doi:10.1002/pamm.200700645. ISSN 1617-7061.
  15. "JFE steel" (PDF). සම්ප්‍රවේශය 2012-10-20.
  16. 16.0 16.1 Douglas C. Giancoli (1995). Physics: Principles with Applications (4th ed.). London: Prentice Hall. ISBN 978-0-13-102153-2.
    (see also Table of Resistivity. hyperphysics.phy-astr.gsu.edu)
  17. John O'Malley (1992) Schaum's outline of theory and problems of basic circuit analysis, p. 19, McGraw-Hill Professional, ISBN 0-07-047824-4
  18. Glenn Elert (ed.), "Resistivity of steel", The Physics Factbook, retrieved and archived 16 June 2011.
  19. 19.0 19.1 Hugh O. Pierson, Handbook of carbon, graphite, diamond, and fullerenes: properties, processing, and applications, p. 61, William Andrew, 1993 ISBN 0-8155-1339-9.
  20. Y. Pauleau, Péter B. Barna, P. B. Barna (1997) Protective coatings and thin films: synthesis, characterization, and applications, p. 215, Springer, ISBN 0-7923-4380-8.
  21. Milton Ohring (1995). Engineering materials science, Volume 1 (3rd ed.). Academic Press. p. 561. ISBN 978-0125249959.
  22. Physical properties of sea water සංරක්ෂණය කළ පිටපත 2018-01-18 at the Wayback Machine. Kayelaby.npl.co.uk. Retrieved on 2011-12-17.
  23. [1]. chemistry.stackexchange.com
  24. Eranna, Golla (2014). Crystal Growth and Evaluation of Silicon for VLSI and ULSI. CRC Press. p. 7. ISBN 978-1-4822-3281-3.
  25. 25.0 25.1 Transmission Lines data. Transmission-line.net. Retrieved on 2014-02-03.
  26. R. M. Pashley; M. Rzechowicz; L. R. Pashley; M. J. Francis (2005). "De-Gassed Water is a Better Cleaning Agent". The Journal of Physical Chemistry B. 109 (3): 1231–8. doi:10.1021/jp045975a. PMID 16851085.
  27. ASTM D1125 Standard Test Methods for Electrical Conductivity and Resistivity of Water
  28. ASTM D5391 Standard Test Method for Electrical Conductivity and Resistivity of a Flowing High Purity Water Sample
  29. Lawrence S. Pan, Don R. Kania, Diamond: electronic properties and applications, p. 140, Springer, 1994 ISBN 0-7923-9524-7.
  30. S. D. Pawar; P. Murugavel; D. M. Lal (2009). "Effect of relative humidity and sea level pressure on electrical conductivity of air over Indian Ocean". Journal of Geophysical Research. 114 (D2): D02205. Bibcode:2009JGRD..114.2205P. doi:10.1029/2007JD009716.
  31. E. Seran; M. Godefroy; E. Pili (2016). "What we can learn from measurements of air electric conductivity in 222Rn ‐ rich atmosphere". Earth and Space Science. 4 (2): 91–106. Bibcode:2017E&SS....4...91S. doi:10.1002/2016EA000241.

භාහිර සබැඳි සංස්කරණය