The above Ad will no longer appear after you Sign Up for Free!

Conductivity

Discussion in 'Question of the Day' started by Radman, Apr 25, 2006.

?

What is the percent electrical conductivity of copper?

  1. 48%

    0 vote(s)
    0.0%
  2. 56%

    0 vote(s)
    0.0%
  3. 66%

    5.6%
  4. 73%

    11.1%
  5. 89%

    66.7%
  6. 100&

    16.7%
  1. Radman

    Radman Well-Known Member

    Messages:
    1,219
    Likes Received:
    10
    Location:
    Franklin, TN
    No response required, simply do the poll! After a while I'll put up the answer if nobody else felt like explaining it before I get to it. This one's fairly easy too.
     
  2. Radman

    Radman Well-Known Member

    Messages:
    1,219
    Likes Received:
    10
    Location:
    Franklin, TN
    All right, now who can back up their answers? (Oh and FYI the 100& should be 100% that was a typo.)
     
  3. kingfisher1

    kingfisher1 Active Member

    Messages:
    377
    Likes Received:
    1
    I guessed rather the google it, but it seems to me that copper was a pretty darn good conductor yet some of the energy put in had to turned into heat (second law of tehrmodynamics?) so 89% seemed logical...
     
  4. Radman

    Radman Well-Known Member

    Messages:
    1,219
    Likes Received:
    10
    Location:
    Franklin, TN
    This brings up a good point I forgot to mention, these answers may be slightly rounded or approximate.
     
  5. Mayhem

    Mayhem Senior Team Emeritus Premium Member

    Messages:
    1,790
    Likes Received:
    5
    Location:
    Australia
    Have not taken the time to look it up but I have a strange recollection that aluminium was originally considered the ideal conductor of electricity but since that copper is a much more efficient conductor it has a rating of 100%. In saying that, it is quite likely that I am wrong.

    However, given that I do recall that it was given a 100% conductivity rating in the standards, there must be some reason why resistance isn’t considered.

    Then again, given that you can never expect to transfer energy with out some form of loss (why we have never been able to achieve perpetual motion), the 100% rating may come from the fact that it has the lowest resistance of other conductors and is therefore used as the bench mark.

    Suppose I should really go and find a reference to back this up. Perhaps I will do so over the weekend, unless someone else beats me to it (hint hint).
     
  6. Chris15

    Chris15 CBMod CB Mods Premium Member

    Messages:
    4,141
    Likes Received:
    421
    Location:
    Sydney, Australia
    I thought that gold was a better conductor than copper... and Aluminium is used for HV transmission lines around a steel core for strength.
     
  7. Mayhem

    Mayhem Senior Team Emeritus Premium Member

    Messages:
    1,790
    Likes Received:
    5
    Location:
    Australia
    Neither gold or aluminium are as good at conducting electricity as copper. Gold is used because it does not corrode. Aluminium is used over copper in some applications because it is stronger. Brass is used for the same reason.
     
  8. Chris15

    Chris15 CBMod CB Mods Premium Member

    Messages:
    4,141
    Likes Received:
    421
    Location:
    Sydney, Australia
    If I consult my SI Data Book, copper has aconductivity of 57.9. There is one element with better conductivity, that being silver, with a conductivity of 60. The unit is MS/m. 1 MS/m = 1 / (1 micro ohm * 1 metre) = 1 / 0.01 micro ohm centimetres. (
     
  9. Radman

    Radman Well-Known Member

    Messages:
    1,219
    Likes Received:
    10
    Location:
    Franklin, TN
  10. Chris15

    Chris15 CBMod CB Mods Premium Member

    Messages:
    4,141
    Likes Received:
    421
    Location:
    Sydney, Australia
    I would tend to think that copper is not 100% conductive, else it would not have any resistance at all, and we know that it is not true. Superconductors are the only instance of practically zero resistance, and then only at temperatures within few degrees of absolute zero.
     
  11. Radman

    Radman Well-Known Member

    Messages:
    1,219
    Likes Received:
    10
    Location:
    Franklin, TN
    This may explain the discrepencies: Conductivity


    It says specifically of intrest
    So I suppose this may be what Belden was referring to on that exam. (That was a rephrasal of a question off their Belden Cable College "Cable 101" Exam.)
     
  12. Radman

    Radman Well-Known Member

    Messages:
    1,219
    Likes Received:
    10
    Location:
    Franklin, TN
    Just noticed that you haven't even voted! ;)
     
  13. Chris15

    Chris15 CBMod CB Mods Premium Member

    Messages:
    4,141
    Likes Received:
    421
    Location:
    Sydney, Australia
    Correct. Is there a problem with that? ;) But I guess if the standard against which conductivity is measured is copper, then I guess it would be 100%. Then silver would have a conductivity of 104%! I have issues with the question (like percent of what) and I know that you have taken it from elsewhere, so I will not blame you for it, but I am withholding my vote at this point.
     
  14. kingfisher1

    kingfisher1 Active Member

    Messages:
    377
    Likes Received:
    1
    It seems to me that 100% is measure agaist copper, makiing copper not the most conductive things around but the bench mark to which everything else is compared. is a bit like tempature. O degrees Celsius isn't an absense of a quantity. temputrue is jsut a scale that compares one things heat to anothers heat (in celius' case it being water)
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice